Panty Shot - Mentioned more often than explicitly shown, but still there - One of Hayate's duties becomes to prevent this with Nagi (who wears short skirts quite often) and when he isn't there, itshows.
Plus, Himegami's idea of a weird eye mask that does nothing to hide his unique hair and his "pseudonym" of 'Princess God' isn't fooling anyone.
And Nagi showing up to rescue Hayate wearing a silly domino mask and calling herself "Mask the Money".
Also, Klaus makes a cameo in the Butler Battle Tournament with Tama, both wearing nothing different from their usual clothes, except they're both wearing a Power Rangers/Super Sentai mask. Also subverted in this one, because except for Maria, nobody knows it's him.
Maria and Saki show up as the 'Max Hearts'. All that the costume is is eyewear. They both realize (and comment) on how paper thin the disguise is. Nagi didn't see through it, and wanted to get their autographs.
Alternately, Chiharu's 'disguise' as Sakuya's maid 'Haru' seems solid enough that they don't recognize her in the least.
Maria wears her old school uniform in episodes 6 and 7 of season 2 to infiltrate her alma mater and find out where Hayate is staying after all the people he gave the million yen to return it out of guilt to the mansion. Unfortunately it draws a lot of attention, and putting on stylish glasses only enhances her beauty. She settles for Opaque Nerd Glasses, and fools Hayate briefly, although he eventually figures out it's her.
Parental Abandonment - Hayate Ayasaki, whose parents sold him to the yakuza very nice people to pay off their 156,804,000 yen debt and ran away
Nagi Sanzen'in, whose parents are dead
Her father is never seen ( except in Can't Take My Eyes Off You and Cuties) and supposedly died before Nagi could remember him. She has a few memories of her mother though.
Her grandfather is said to have given her some raising, but she is estranged from him from the start and then she gets cut off from the inheritance. Mother figure is Maria.
Hinagiku happily lives with her (and her sister's) adoptive parents, though only their foster mother has been seen.
Sakuya's family also appeared during her birthday party. Both her father and her little siblings are comedy-obsessed-crazies just like her. Hell, her father's even worse.
Presumably her mother was with the other two children during this event. She lives, and presumably was raised by her two butlers.
Wataru Tachibana has living parents, but runs the family business and lives alone with his maid.
His mother is shown to have been living in Las Vegas and his father in some other eastern country.
Athena, whose parents are dead, mentioning this is Athena's berserk button.
Isumi's female family (up to her great grandmother) has been shown, but no mention of her father, grandfather or great grandfather has been made.
Isumi only has one grandfather, one great grandfather, one grandmother and one great grandmother? Eww.
Isumi apparently has no paternal family tree period
Izumi lives with her father (and it is implied that her mother is simply not shown.)
Riza lives with her grandfather, though her father may have been seen, it isn't mentioned.
Miki is implied to live with her parents, but they have not been seen.
Both of Chiharu's parents are shown to be around, but are neglectful to the point of eventually burning down their own house in a money-making scheme.
Both of Ayumu Nishizawa's parents are shown, and are decent folk.
And now Luca. "I thought that you had no relatives left ... when both of your parents ran away after dropping the debt on you...." By this point, you could pretty much call this work "Parental Abandonment: The Manga".
Parental Substitute - Hinagiku to Athena. Holy. Shit. Basically there's a little girl who may or may not be an aged-down Athena who appeared on the campus out of nowhere and bumped into Hinagiku. When the others asked where her mother was she pointed to Hina and said "Mama". Cue absolutely everyone in the panel being completely stunned. Knowing Hata...and the advice Hayate got earlier in the chapter...there is a very good chance that Hayate will be playing dad, which will result in mind-blowingly-large Ship Tease with him and Hinagiku.
Confirmed, Hayate is announced to be her father. Hinagiku was chosen as the 'mother' because of the sword she carries.
Although Nagi wishes he were more of a boyfriend, Hayate seems to be playing this role for her. Maria is her mother figure, though the role originally seemed to be that of big sister.
Hinagiku and Yukiji found the Katsura's to be both willing Parental Substitute and get to play the Happily Adopted card when their parents dropped a large debt on them and disappeared.
In the character profiles, Sakuya is said to have been raised by her two butlers and her nurse, instead of her parents, while also serving as the parents to her siblings.
Perpetual Poverty Hayate. 150,000,000+ yen debt aside, if he is ever given any money he will certainly lose it. Even people around him seem to spontaneously lose money just by being in his proximity. Later chapters of the manga even give him the title God of Poverty. He notices this trend, and is quite dismayed.
Hayate becomes explicitly flat broke at least five times in the manga.
The first is when he has to spend a few days out of the mansion and manages to lose 1,000,000 yen in a few hours mostly helping people in trouble; he ends up broke, without a coat, and depressed in the snow when Hinagiku finds him and invites him over.
The second is when he buys Hinagiku a birthday present, partially to repay all the help she has given him, and also buys Nagi a hair-clip in a rare bout of forethought knowing that she would be jealous as well as a stuffed animal for Maira as thanks for her help as well.
The third time is when he tries to get Ayumu a White Day gift and accidentally gives it to Maria when he tries to practice what he's going to say; Hinagiku and later Maria helped bail him out.
The fourth time is when he winds up taking Hinagiku out on what both would - eventually - find out is a date and when the movie tickets he was given fall through he steps up and gets tickets to what is very obviously Disney Land Tokyo.
The fifth time is in Greece when Hinagiku saves him by curb-stomping Gilbert in (what is more-or-less) beach volleyball and he takes her to a very fancy restaurant as a way to pay her back...thankfully Maria knew the place and made sure they would only charge him the money that he actually had.
Perverse Sexual Lust - Parodied. Hayate yells, "I only like 2-D girls!" to get Nishizawa to leave him alone.
Pervert Dad - Izumi's dad likes making his daughter do cosplay as a form of punishment and jumps at any other reason to see her in a costume. A flashback also revealed that he was just a little too pleased when his kindergarten-age daughter innocently stated that she wanted to marry him.
Please Don't Leave Me - Although the romanticism is questionable, Nagi uses this in typical tsundere method by implying that Maria and Hayate will eventually leave her (presumably for romantic relationships), and after convincing attempts are made by Hayate, she 'allows' him to continue working as her butler.
The Power of Love - Church Militant Sonia requests a kiss from Wataru if she rescues Saki, who had just been kidnapped. Wataru pays in advance. Next page, Hayate (on bike) catches up to the flaming wreck of the kidnappers' car: a giant cross driven through the hood, the men tied up nearby, and Saki unhurt but confused.
Promise - Hayate has promised to always protect Nagi, and to always love Athena.
Hayate also made a promise to Hinagiku to give her a present on her birthday. It doesn't seem like much but it meant a lot to Hinagiku, enough so that her emotions began to build up and confuse her as she started dreaming about Hayate and not knowing why. When he forgets this promise and she winds up spending several hours waiting for him it triggers her deep-seated fears of abandonment (amplified by Wooden Masamune) and she mentions this promise and her confusing feelings as she chews him out before she can regain control of her emotions. Fortunately for them both, things turned out all right in the end.
The end of chapter 396 has Hayate make the most serious promise of the series: To marry Luca if she wins the doujinishi competition. And yes, he fully intends to keep it if she does.
Prince Charming Wannabe - Played for comedy, Kyonosuke Kaoru is this for Yukiji Katsura. She actually seems to have a fondness for him, but he seems to think he needs to sweep her off her feet, which causes her to reject his advances.
Puppy-Dog Eyes - Nagi (or really, any girl) going all sniffly and teary-eyed will cause Hayate to not just steel his resolve and do whatever's necessary to make them happy, but will adamantium his resolve. We learn why during "The End of the World" - he took Athena's advice to heart.
Punch-Clock Villain: The very nice people. The spend the first few chapters chasing after Hayate to settle his debt. However once Nagi pays it off, they later approach Hayate and chat amiably with him, apologize for the whole ordeal, and even offer to buy him lunch.
Racing the Train - Hayate, of course, when he winds up taking Nishizawa to the Shimoda hot springs using her bike while the rest of the crew takes the train. At first Nishizawa remarks on the nice weather and the breeze before realizing that they are going waaay too fast. Hayate casually tells her that they caught up to the train and to wave to the others. Nishizawa hangs on for dear life and points out that they are ahead of the train. This was a bullet train mind you, and he's riding an ordinary bicycle. Apparently this is because he used to be a bike courier.
Relax-o-Vision - Hilariously inverted in Chapter 221 where Hayate beats up Gilbert yet again for bothering them while they were on vacation in Greece. Instead of soothing images, it shows some pretty brutal shots of faceless characters punching each other (with over-the-top blood spurts). And the caption, "as this portion portrays extreme cruelty, please enjoy these images".
The Reliable One - Hayate of course, being a rare case of the main character being this. Since he is a butler and a good portion of the cast are rich but socially naive girls and an assortment of wacky and highly unreliable people this makes sense. When he isn't being focused on, he can even be seen doing...well darn near anything really. He steadily acquires more girls to support and helps them with their problems as well as handling minor chores and such that often goes unnoticed (though the girls are pretty observant and very grateful for his help).
Maria was this toward Hayate and Nagi in the beginning as the reliable older figure (only by a year)who came in to sort out a mess in a few panels whenever messes got too big due to Hayate's abysmal luck. This has been somewhat phased out as Hayate has gotten more accustomed to the job and Maria's own quirks were dialed up a bit for humor.
Hinagiku becomes this to Hayate over the course of the series. They start out as friends, but eventually Hayate starts going to Hinagiku for all of his problems, especially those he didn't want one of the other girls to know about and typically finds out about the messes he didn't want her to know about either. It helps that she's more proactive about it and prone to worrying about him when he's acting off and thus tries to find out the problem on her own to help the poor guy out.
Reptiles Are Abhorrent - We can't quite be sure how the series feels about this trope. Machina's alternate form (we think) is a giant snake, and his first acts include nearly killing the main character and acting like an all around bad guy. But as of ch 255-ish, he's being more than friendly with the heroes, even jokingly (we think) asking Maria to marry him for her (and Sakuya's) hamburger-making skills.
Rescue Romance - Hayate should be the God of this. He helps people out all the time, even when it's not his job, and Chapter 273 showed us that if Hayate helps a girl with a problem in some way (up to and including saving their life) there is an incredibly high chance of that girl developing feelings for him...one guy seems to have fallen for him this way even! It's actually hard to find a ship in this work that doesn't involve this.
While Nagi and Hayate's relationship has shades of this, it might not exactly count since she fell in love before he rescued her when she thought he was asking her out (because Hayate is the worst criminal ever). This applies better to how Hayate met Hinagiku as he...at least tried to help her down from the tree, but was practically invoked afterward when he told Hinagiku that he would come save her if she ever called for him...and delivered on that when they were both in the haunted building at school.
Unbelievably, Yukiji of all people actually gets in on this too. Apparently she was totally wasted (as usual) one night and stumbled across Ashibashi-sensei who was getting harassed/mugged. After defeating the thugs with ease, it seems that Ashibashi might have fallen for her...especially after stopping by Hakuou the next day and successfully picking her up in his awesome sports car. Currently Yukiji is oblivious to this new possible romance (as is standard for this series) and Kaoru-sensei is left speechless that a love rival has shown up.
Even shows up in places you wouldn't expect. Wataru fell for Isumi when she saved him an Nagi from a cockroach. Izumi promised to marry Hayate when he saved her teddy bear from a dog during End Of The World. He doesn't remember this and she only did recently
Retcon - The first episode of the second season establishes that only a month has passed since Hayate became a butler, placing the entire first season into a vague quantum state of semi-nonexistence. Or something.
The first season veered off the manga's path sometime after Hayate entered Hakuou. The second picks up the actual storyline from where it left off.
Right Behind Me - Hinagiku gets clobbered by this in the current arc (starting at chapter 300), it's not quite the same effect of having Hayate himself hear her confession, but it does give blackmail bait.
Romantic Two-Girl Friendship - Miki has been pushing a one-sided version of this with Hinagiku, apparently since they were in grade school. Hina has been friends with Miki for ages, but makes the boundaries very clear. Miki does respect this for the most part, but sometimes she can't seem to help herself such as when it involves Hina in the bath or the possibility of seeing her in a bikini.
However, despite her firm boundaries with Miki, Hina seems to have had a relationship like this with Athena. She describes being awed by Athena's beauty and had an awkward introduction full of blushing and stammering, but the two became very close and were said to be the school's unstoppable duo. This is particularly notable since before then (and until her Birthday Arc) Hinagiku pushed anything close to romance aside due to her past and fears. On the other side, Athena was shown to be unapproachable to anyone else and seemed to be pushing others away since the End of the World Arc.
Hinagiku and Chiharu's relationship takes on shades of this in Chapter 405 with them spending the entire day together in Kyoto. Chiharu brings out a teasing and playful side that she doesn't seem to show around anyone else thus far, Hina appears to be quite open with Chiharu and even has a nickname for her (Haruko-san) which she doesn't seem to use when others are around. And of course there is the scene where Chiharu gets quite nervous when Hina asks why she's wearing her glasses in the bath, which results in intense blushing, staring, and sputtering denials as Chiharu watches Hina casually get into the bath right in front of her.
She also seems to be powered by rice, has particularly expensive tastes, and her talents are mostly not sleeping, being connected to the Internet 24/7, and playing video games. Maria and Nagi complain about using all of humanity's ingenuity just to make shut-ins.
Room Full of Crazy - Chapter 407 the SC Rangers are filming a video and need feel the need for something more "shocking". So Izumi suggests they go film Kotetsu's room. Given that Kotetsu is an avid photographer and Hayate's self-professed stalker, it comes as no surprise that the entire room is literally covered in various-sized pictures of Hayate. What really sets the creepiness factor up a few more notches is the fact there there is literally nothing else in it except his bed. Risa and Miki definitely find it creepy. Izumi finds it "pure love".
RPG Elements: Happens on a regular basis. Hayate does a lot of dungeon crawling.
RPG Episode - Filler episode where the Student Council trio gets sucked into an old RPG after the game gets fed up with all the insults being heaped upon it.
Running Gag - Whenever a character is near-broke, it has become a running gag to leave them with 12 yen. (One 10 Yen coin and Two 1 Yen coins)
There's also the matter of Hayate girlish face and being forced to crossdress; it's gotten to the point that it actually seems to be plot-relevant that if someone met him while he crossdressed there would be no way they woulds know he was a guy (as proven once by Kotetsu and again later with Luca.
A common meta-gag for years was that Hayate was never around for Hinagiku's Fanservice moments, leaving him with almost no instances where he saw Hina in various states of undress despite it being a common gag with him and the other girls. This coincided with several years of Hinagiku being just about the only character to not see Hayate any time he was forced to crossdress - the one time she did was all the way into the Greece Arc and ended up being off-panel so the readers never saw her reaction unlike with the other girls.
Hata seems to have taken notice of this as the situation got flipped around after the Greece Arc. Now Hayate has plenty of moments where sheer coincidence conspires to have him catch Hina undressed. He even sees more than the readers do and is heavily implied to walk in on Hina changing regularly off-panel. The fact that Hayate knows she's changing behind that door and keeps opening it...
Another even more meta joke is the nigh-impossibility of Hinagiku ever properly confessing her feelings to Hayate. Hata-sensei picked up on this one too and wound up having Hina confess and/or propose to Hayate at least four times in one chapter...but each time the meaning was lost because she couldn't bring herself to say it in a direct manner (she even broke out the old Showa Era "I want to eat your miso soup every day" which even the narrator notes would be completely misunderstood, unless they watched Maison Ikkoku).
Hayate and Hinagiku's incredible similarities started on the level of Birds of a Feather and eventually morphed into a gag unto itself. Even the anime joked that Hayate and Hinagiku could secretly turn out to be siblings. By the later part of the manga you can bet that if Hayate is shown to have a trait, characteristic, or talent, then Hinagiku will be shown to also have it within a couple chapters and vice versa. One example is when Hayate is seen to be a Big Eater for a contest at the end of summer break and not long after Hinagiku is shown to be able to eat just as much on the Class Trip...the same chapter that reveals both Hayate and Hina are Olympic-level snowboarders.
Hayate's bad luck drives entire plotlines and provides much of the humor in the series, especially as everyone is aware of it.
It Runs in the Family - Though we've only seen the female half of the Saginomiya family, they're all pretty well CloudCuckooLander. Isumi is the closest one to sane, and she barely qualifies as such.
Isumi's grandmother mistakes Isumi's mother — her own daughter! — for Hayate when meeting him for the first time. And the mother thinks she actually is! Even wondering where she went when the grandmother changes paths.
Sakuya's family is just as comedy-obsessed as she is.
Screw the Rules, I Have Money! - Nagi is not even remotely above solving her problems by throwing her ludicrously vast fortune around. Inverted with the Yakuza, who only start to obey the rules when they get their money. IE, they don't just kill people for fun; it's Nothing Personal.
During the school marathon, Klaus is set to fight Himuro, instead of pulling out a weapon, he pulls out a briefcase of money, and wins.
Himuro actually bleeds from the mouth as he concedes defeat.
Security Cling - Nagi does this several times, mostly to Hayate. Hinagiku is another favorite target for this, sometimes even when Hayate is also present. Most often it's someone hiding behind one of them for protection but the clingy-ness is definitely there.
Hinagiku even once did it to Hayate when they were in the haunted old building at school late at night but she was just kidding and was messing with him due to her intense dislike of losing (triggered by getting scared earlier and getting saved by Hayate). Hayate even makes a Call-Back to this around 200 chapters later, though he claimed he was also kidding, it's a cover for it actually being a Security Cling but instead because he was scared and wanted to protect her from Tama. Her reaction was that of a typical Tsundere.
Hinagiku had a short one even earlier in chapter 45 where she clings to Hayate after he comes out of nowhere to save her from a monster in the haunted school building. Hayate's face completely lights up and he stutters trying to think of what to say. The next chapter has Hina making Hayate swear to never tell anyone (as an after-thought as she was more concerned about people knowing she was scared of the monster due to her pride as Hakuou's Student Council President).
Nagi also does one to Ayumu in Chapter 215 after they wind up alone in a dark cave in Greece. She was actually fine up until Ayumu turned the flashlight off...right after she recalled that Nagi mentioned not being good with dark places.
Serious Business - Butlers must be ready to defend their masters with their lives, and Hayate's superhuman feats are apparently the bare minimum for a butler—heck, he doesn't even have a master sword technique that sets stuff on fire!
Satellite Love Interest - Koutarou Azumamiya used to be this for Hinagiku originally, and the anime even added a few episodes of this to him, but since the second year started, he's actually gotten some character of his own as the story develops him slightly in regards to his relationship with his butler, who is going to a university overseas.
"Shaggy Dog" Story - The show devotes an entire episode to these, where the cast takes turns telling various stories with no point.
And that episode is based on a manga chapter.
Hayate goes to the Church of Alexander Mark to prove himself in the Tiger's Pit. There is no Tiger's Pit, but there is a very dangerous dungeon that Hayate gets lured into by a fake nun who tells him it's the Tiger's Pit.
Shamu Fu - During an ocean cruise the boat they are on starts to sink (it was basically a clone of the Titanic so it was hardly unexpected) Hayate ends up in the lower levels, injured and in danger of being eaten by a giant shark with poor Isumi trying to save him by waving a pathetically small stick. As soon as Nagi jumps in to help him he recalls there were two sharks. When Nagi's attacked by the other one, she has about a couple seconds to be afraid before Hayate brains it with the first shark effortlessly taking them both out in out hit.
She is all Grown Up - Actually seems to have been inverted , Hayate doesn't seem to have noticed A-tan's growth when he meets her after ten years of separation, until he's directed to look via an extremely obviously loaded question...and even then it seems to take him a moment. This is particularly funny as they met when they were children and she's now one of the most developed girls in the cast. Interestingly, he actually seems to prefer the memory of the younger Athena too.
She Cleans Up Nicely - During the Greece Arc, Hayate winds up trying to pay back Hinagiku to show his appreciation for all her help. To do so he takes her out to a very fancy restaurant and tries very hard to put aside his troubling plot-related thoughts to ensure that she has a wonderful evening. He needn't have bothered as Hinagiku showed up a moment later wearing an elegant dress and looking literally stunning. As in Hayate's thoughts just stopped and he wound up staring at herfor a few minutes until she brought him back to reality.
Shinigami - Several characters have stated that Hayate must be being followed by one on a regular basis, this is probably never actually going to come up again...maybe. It's been joked on forums for a while now that it's probably a girl and that he's taking 'flirting with death' rather more literally than most and that with all the comments about him dying young and being fated to a horrible death she may just be the "winner" of the Unwanted Harem in the end.
Shipper on Deck - Many on several different levels, particularly confusing as some of the supporters also have crushes on one (or both even) members of the couple their trying to pair up - this creates an extremely weird M.C. Escher-esque...thing...of interlocking love triangles, squares, and other shapes.
A more straightfoward case would be Mrs. Katsura. She very clearly supports Hayate/Hinagiku and even told Hina already that she would gladly accept him as a son-in-law, as well as leading to one of the major Hayate/Hinagiku moments by telling Hayate when Hina's birthday was and that he should get her a nice present. Sadly even this example becomes complicated by the fact that Mrs. Katsura is just a little too fond of Hayate.
Ship Sinking - Chapter 265 apparently sinks Athena X Hayate. But in the best way possible! note Of course, given the fact that the mangaka is a Teasing Creator and certain spoiler material, who knows where this might go.
And then comes chapter 266 with Athena deciding to go back to Japan after all. Teasing Creator indeed.
It also appears that the Wataru/Isumi ship has been sunk as well with him seeming to get over her in a similar manner to the above example.
Hayate with everyone. (Well, at least half the cast.)
Shoo Out the Clowns: Halfway through Can't Take My Eyes Off You! is when the anime's arc kicks into high gear, and gets more serious. It's also the point at which the humorous intros, outros, and commercial bumpers disappear.
Shorttank - Hinagiku Katsura could be considered for this, though she tries to impress the fact that she is feminine while her friends try to convince her she acts more like a guy. She seems to prefer the female school uniform in most cases, wearing a pair of sports shorts underneath (to keep guys from looking up her dress apparently). She's been shown continually to have feminine tastes for cute things and seems extremely embarrassed when the guy she likes notices that she is feminine.
Chapter 352 has everyone in the Violet Mansion except Hayate getting colds. Hayate tends to them and decides to go out to get medicine for them, given his luck he is sent flying by Kayura and hit by a speeding truck. Despite this he seems okay and returns with the medicine.
Chapter 353 then has Hayate catching the cold as well, and unfortunately for him it's also the day of the Hakuou final exams (that being the "punchline" to the previous chapter). He can't take medicine since Nagi would have felt bad about giving him her cold. And he can't just coast since Hinagiku is expecting great scores from all their studying together. The rest is an escalating set of disasters that makes his cold worse and kills any time he had to prepare. Thankfully Maria figured out he was sick and let him rest when he got back.
Hinagiku gets very badly sick while all alone in Chapter 388, causing her to remember the same thing happening when she was little. This time, however, when she calls for help Hayate instantly shows up to care for her. At first it's played for heartwarming Ship Tease then then Hilarity Ensues. It actually continues into Chapter 389, where Hina realizes she's going to be all alone with Hayate for the night. Cue a massive blush and little angel and devil Hina's popping up to give her advice; the angel saying to just sleep while the devil says to get Hayate to spoil her, like peeling an apple for her. She rolls over to go to sleep...and then asks Hayate for a peeled apple cut like rabbits.
It turns out that Hina being sick and suddenly relying on him like this causes Hayate to recall Ruka's recent confession. He notes that would make it seem like there was something with Hinagiku too, then tells himself that it could never happen once again. He's then surprised when Hina wonders why he can't always be that nice and tells him that he's always focused on Nagi, which he surprisingly considers. She then tells him that she wishes he'd occasionally treat her like his lady and asks him to hold her hand as she falls asleep. Hayate does so as he convinces himself that nothing would happen even if he holds her hand like this. He then calls her Oujo-sama just as the Moment Killer opens the door.
Single-Stroke Battle - Several times in the series, usually Hayate or Hinagiku showing off why there isn't much in the manga that can genuinely threaten them.
Chapter 465 gives an excellent one between Hayate and Klaus, who had up to this point never accepted Hayate as Nagi's butler and wanted to settle things with a sword duel. Too bad he told Hayate it was for Nagi's sake and to not hold back...and that Hayate revealed he bought the girl's stun gun from the previous room...
Skinship Grope - Hinagiku seems to be a common victim of this as Even the Girls Want Her, with Ayumu at the hot springs (played up more in the anime) and with Miki in Greece being the two biggest examples, though the Student Council Trio seem to like doing this to Hinagiku at other times as well. Hell, Miki even uses this by name when she surprises Hinagiku in the bath while claiming that their skinship is far too low. Hayate becomes a victim as well whenever Kotetsu appears unexpectedly, with the public bath trip in 304 being the best example yet.
The Slacker - Those Three Girls, Miki Hanabishi, Izumi Segawa, and Risa Asakaze, actually take this to the level of barely staying within the relevant plot of characters. Izumi is the only one who's actually shown interest in Hayate, Miki has actually disdained his interest (sometimes) and Risa hasn't seemed to decide whether she wants to be interested or not. All three love to hang out with Bottle Fairy Yukiji, actually attempt to keep their grades barely above failing and only seem to show up often enough to cause trouble for the chapter to revolve around.
Sleep Mask - At least in Season One of the anime, Hinagiku Katsura wears one of these on a plane ride. Not as a personality statement but because she's utterly terrified of heights. She's not even sleeping, she just uses the mask (along with being wrapped in a blanket with at least six seat belts) so that she doesn't have to see how high up she is...
Society Is to Blame - Hayate uses this trope when trying to explain his reasoning for attempting to kidnap Nagi. Only the fact that he fails, horribly, and then saves her from real kidnappers, getting her to take him on as her butler saves him, and starts the real story.
Spider-Sense - Hayate seems to have something like this that tells him to react even when he's distracted, however it also fails him frequently for the sake of comedy.
Hinagiku has one as well, specifically she has a super precise spiritual sense that allows her to feel the presence of spirits and such that she can't see. In Chapter 360 she uses it to track Father Lynn when she tries to hunt him down. Hayate is at first amazed by her sense when she can tell he's in the room with them (even nearly taking him out when he first appeared) and can immediate tell when he leaves, but finds her perception frightening when he can pinpoint where he went.
Stalker with a Crush - While Athena watching Hayate from afar is more like schoolgirl pining, Chapter 304 reveals that Kotetsu has become this when he follows Hayate into the public bath and directly states this as the reason why he is there. Surely one has to at least admire his tenacity if nothing else.
Strip Poker - In chapter 434, Miki reveal that she had her father's company make a deck of cards where half of them were transparent, creating some interesting new strategies since your opponent could see at least some of your cards and vice versa. Hinagiku shows up after a demonstration and wants to play, with Mikiinstantly declaring that Hina has to strip if she loses...and making Izumi strip instead of herself if Hina wins. After some obvious goading to her competitive nature, Hina agrees. Miki realized how screwed she was when Hina got an all-transparent royal flush. For Fanservice Izumi did actually strip after each hand despite her complaints.
And Luca was one when she was trying to go to High School.
Subordinate Excuse - Pretty much the real reason that Hayate is employed, at least as far as Nagi believes. In truth, she gushes over him in private while he remains cheerfully unaware of any perceived romance on Nagi's end.
This seems to be the case with Chiharu in regards to her part-time job as Sakuya's maid and possibly as the student council secretary. She apparently took both jobs because she likes to "support cute, amazing girls". She's shown to be quite caring towards Sakuya and doesn't have much of a reason to be her maid other than taking a liking to her and wanting to help her. Chiharu has also voiced her admiration of Hinagiku, though their relationship is more professional...at least until Chapter 405 where Chiharu turned playfully teasing to Hina and is heavily implied to be crushing on her after the scene in the baths.
Summon to Hand - Parodied with Hinagiku summoning the Wooden Masamune blade, which is Isumi's family sword. In an omake segment Isumi laments that the sword keeps disappearing, which we see is because Hinagiku spots trouble and calls for the Wooden Masamune to go save the day. It instantly answers her summon because it's fond of her apparently.
Sadly we aren't sure what's happened to Wooden Masamune now that Hinagiku has obtained the Shirosakura sword, marking her as an Ally of Justice to boot, and has been summoning it ever since instead. Last we saw, Hayate had used Wooden Masamune to beat King Midas so either he has it now (he is a highly skilled swordsman after all) or it's gone back to Isumi's place for now.
Supernaturally Delicious and Nutritious - Of course Hayate has delicious supernatural blood. It's part of the His Life Sucks package. In fact, his blood when he's half-dying is one of the most mystically infused substances in the world; and can completely power up Isumi or her grandmother. The latter has no problem with snacking on him, while the former tends to abstain, but once when Nagi was in danger, she tasted just a little and that gave her enough power to both break a Power Limiter curse that was on her and use her magic powers to teleport Hayate onto a spaceship in freaking Outer Space.
Super-Powered Robot Meter Maids - Up there on Hayate's nemesis list, what do you mean flight and missiles aren't required for a robot butler to clean the house?
Hayate: Is he really made for nursing?
Klaus: I'm sure it's necessary equipment for women living alone... Like a protection against stalkers!
Nagi: Sounds really fishy.
Super Window Jump - One of many feats Hayate can do that borders on the supernatural.
Surprise Santa Encounter - An imaginary Santa representing Hayate's morals and work ethic. Later it is revealed that, Mikado was Santa.
To say nothing of Santa Conan suddenly appearing in a one-off chapter.
In episode 24 of the first season, after retrieving a clothing article for her, Isumi hugs Hayate and says she loves him. Nagi and Wataru see it, and aren't too happy about it. Nagi later asks him if he loves her, and thinking Isumi likes him, later runs away. She then decides to go to Isumi's mansion to ask her if she likes Hayate, and sees him apparently embracing (in actuality he was searching for Nagi, and came to Isumi's place, and she had some dust in her eyes at that moment). Nagi then goes into Clingy Jealous Girl mode, asks if Isumi likes Hayate, then in the spur of the moment, sells him off to her.
In episode 41 of the first season, Yukiji seems rather serene and calm unlike her usual self. Hina mentions getting some new year's money from her, which her sister had never done before. Yukiji then accidentally drops a resignation letter, causing various characters to assume that she was quitting teaching and leaving. Nagi suspects something seems a bit off, but the others believe today to be the Yukiji's last day teaching them. Hina gets angry with her, feeling she's being abandoned again, and at the end of the school day they plead with her not to leave them. Shiori, the assistant teacher, then begins crying, and it turns out that the resignation letter was hers, and a couple of FlashBacks showed her essentially being Yukiji's slave, hence her desire to quit. However, she thought the students were pleading for her to stay, and decides to do it. Yukiji for her part, turned out to have gotten a bunch of lucky coincidences which really brought her mood up and caused the misunderstanding, and she receives some backlash from her students for the misconception. And the money turned out to be a promise she made to Hina that she would give her some New Years money within ten years, as shown in a Flash Back.
Teen Genius - We're not talking Chiyo's level, but Nagi skipped three grades after all. Hayate actually did start to compare her to Chiyo in the manga, but Nagi told him not to go there.
Nagi and all of her friends, Isumi, Sakuya and Wataru are all at Hayate's grade, while being three years younger than he is. Although Wataru seems to be the most street-smart and least book-smart of all of them.
Isumi is literate in four languages. Nagi in eight. Maria in thirteen. They're surprised to discover neither Wataru nor Hayate can read German.
Maria graduated high school at 13. And was Student Council President two years running, and got the best grades in the school all three years ... what was that about Hinagiku being absurdly perfect?
Hinagiku is implied not to have had the personal tutoring that all of the gradeskippers probably had. And those are the least of her abilities.
Athena is in this group as well, being Hayate's age and having graduated last year, and is already head chairman.
Tempting Fate - Maria gives Hayate an expensive cashmere jacket and tells him not to damage it. Take a wild guess what happens.
Utterly subverted when Hayate wraps it around a tree branch as a safety line to prevent Isumi and the coat from falling into a "Cashmere coat gets really dirty if dropped in" kind of pond. The coat tears apart and he falls in anyway. But at least Isumi and the coat didn't.
Also, when they're on a cruise, Sakuya assures Nagi that the ship won't sink unless they're raided by terrorists. Guess what happens.
It is worth noting that the cruise ship they were on, commissioned especially for that cruise, was named The Titanic, and looked just like its namesake. That ship wasn't just tempting fate, it was actively begging.
Thus far the only time that Hinagiku is able to express her feelings for Hayate was at the end of their first date as the train passing by (which she watched approach) was too loud for him to hear her. When he asked her what she said she tells him, "maybe if you cast a magic spell, you'll be able to hear what I said?". The setting has relatively prevalent magic and Hayate has canonically time traveled. It's possible that he may yet hear that confession himself before the series is through.
Considering Athena/"Alice" knows that Hinagiku loves Hayate, and already expressed a desire to just tell him as it would make things easier, she may be able to cast that spell after all at some point.
In episode 6 of season 2, Maria asks Hayate to stay away from the mansion for a few days due to Nagi being uncomfortable around him after he accidentally sees her naked. She gives him one million yen to live off of for three days, and Hayate worries that he's got too much money on him. He tries to figure out how to make it last, and naturally, he ends up losing it all in one day due to giving it all away. In a subversion, every person who he ended up giving money to returns the money back to Maria after feeling guilty about having taken the money. Which then causes Maria to wonder where Hayate is staying if he no longer had that money on him.
In episode 3 of season 4, Sakuya gives Wataru a 100 million yen investment for his store. Unfortunately, she gave it to him in cash. As Wataru worries about losing it, Hayate shows up, returning a video Nagi rented. The latter then insists on going to the bank to deposit the money, which Wataru is vehemently against due to Hayate's unnaturally bad luck. When Saki says she'll go with Hayate, Wataru reluctantly ends up going with them. Naturally, various hijinks happen along the way with the money.
Hayate and Nagi attempt a surprise birthday party for Ayumu in episode 8 of season 4. He gathers several of the girls together in the cafe, then suggests they leave before she arrives to avoid suspicions. Of course, Ayumu then arrives, and tries to hint that today is her birthday, with Hayate and the others attempting to sidestep it to avoid ruining the surprise.
Things That Go "Bump" in the Night - In Chapter 360, Hinagiku believes she hears one of these while up late in the Violet Mansion apartment and at first tries to wave it off as her being tired. After hearing it again she immediately goes to get Hayate. Luckily it's just Father Lynn messing around, and luckily for him he's able to convince Hayate not to let Hina try "exorcising" him via sword.
This Is Unforgivable! - Although the intentions aren't carried over between meetings, this is often Hayate's manner when Nagi is threatened. Gilbert is frequently the target, and clearly frightened of the consequences of his actions, though not repentant not to try again at a later date.
Those Two Bad Guys - The two thugs who actually pull off kidnapping Nagi, until Hayate's interference, in the beginning of the manga show up later and kidnap Saki from Wataru's video store, until Sonia's interference, have this kind of dynamic between them.
They're also hinted at being the culprits of stealing the money loaned to Wataru by Sakuya, but that was never confirmed.
Third Law of Gender Bending While he has yet to be completely Gender Bent, when Hayate is cross-dressed this trope seems to be in effect, with him acting more feminine than usual. Then again, he has a propensity to act girly regardless of whether he is in a dress or not; wearing a dress just seems to emphasize it.
Tomboy and Girly Girl - Early on, Hinagiku is the tomboy to pretty much any girl she is paired up with (the possible exception being Nagi who seems to be even more of a tomboy and less self-conscious of it than Hina). With character development, Hinagiku has since become much girlier, but still tends to be the tomboy when compared to the other girls she hangs out with.
Enforced Trope: Hinagiku starts out as a tomboy and is contrasted to the more "Ojou-type" other girls of the cast. She does become girlier over time, but mostly when it's just her and Hayate. Her shyness and insecurity causes her to act more like a tomboy when her peers are around and thus she continues to play the tomboy to them in a group setting.
As stated above, Nagi is also the tomboy to darn near every girl in the cast. Her obliviousness to this causes Hayate a great deal of concern as he tries to keep her from lying around in...awkward positions due to the short skirts she wears.
Too Hot for TV: Season 1 due to it airing in an earlier time slot than most other animes of this type.
Trash of the Titans - Chapter 374 shows that this is what Yukiji turned the night duty office into. Substitute/Acting Chairperson Kirika finally decides to start charging her rent over it. Hayate and Hinagiku wind up 'helping' her clean it to keep her from trying to barge into the Violent Apartments.
Trauma Conga Line - For Hayate to not be broken by the hardships of his boyhood life makes him a saint amongst saints.
Trauma Swing - Young Hinagiku is shown to be alone on a swing in an image after her parents have abandoned her.
Although he's not on the swing in the scene, Wataru is shown to be standing in front of a swingset when recieving the papers that will allow him to skip grades with his friends from Sakuya.
Troublemaking New Pet - Shiranui causes plenty of problems when he(?) is first brought to the San'zenin mansion, mostly for Tama who was trying to get the new cat kicked out. Later on he also causes trouble by stealing Izumi's phone when he and Tama are lost in the city and even is seen aiding some ghost cats that were giving Hayate a hard time.
Nagi as a Type A (in keeping with her voice actress and twin pigtails - it's even lampshaded)
Hinagiku is also a Tsundere of the Type B variety, generally playing a kind and supportive role to the students and her friends but brings out the tsun side whenever the Baka Trio become troublesome or when Hayate gets involved in wacky shenanigans and/or sticks his foot in his mouth. She shows a lot of self-restraint and instead of lashing out tends to favor a very intimidating calmness, leading to her being cheerful and kind most of the time, but snarky and annoyed when cleaning up her friends' messes. She often tries to be deliberately more dere only for things to go completely wrong and evoke her tsun side, which frustrates her quite a bit and is a focus in her Character Development.
One short story in the manga had Maria planning to give Hayate a gift, and worrying that she might give the wrong impression ... and then it struck her that she was behaving somewhat like a Tsundere (although she couldn't remember the full term, thinking of it as "tsun-something"). While rehearsing what she'd say, she actually considered the "it's not like I made these for you" turn of phrase.
When Maria and Hayate end up going to the public baths because the boiler is broken, she again delves into Tsundere territory. Especially in the fourth panel....
During a particularly vicious blizzard, Hayate wonders whether it's caused by the Earth being a tsundere.
Hayate himself actually shows Tsundere signs for two people, Hinagiku and Kotetsu. With Kotetsu it's mostly a massive dose of his darker, violent side but he actually has had a couple moments of dere when Kotetsu shows his decent attributes. Hina sees this side of him occasionally as well, usually when he is worried about her. A textbook example happens in chapter 45 in the haunted school building when Hina comments that it's hot and flaps the top of her shirt a couple times to cool off...causing Hayate's face to turn completely red which she then teases him over. Cue Hayate acting like an incredibly stereotypical Tsundere and trying to downplay his interest in her. Unfortunately Hina took his words at face value and didn't read the incredibly obvious subtext (or notice just how incredibly flustered he was apparently).
Hayate brings his Tsundere side out again in Chapter 371: He and Chiharu are shopping and she notices that he seems to be 'the popular type' (he memorizes the girls' likes and dislikes, casually carries the heavier bag, is popular with the older ladies in the market, and matches his pace to the girl he is walking with). He instantly blushes and gives a stuttering denial, then laments that he isn't popular at all as Hinagiku is always getting mad at him. Chiharu tells him that she (Hina) is probably happy having someone always being so casually kind to her to make her feel special...the follow up chapter has him get flustered yet again and mention how he doesn't believe it is possible (talk about denial...)
Twice Shy - Hayate and Hinagiku for the most part. Hinagiku gets easily flustered once love enters the picture and wants Hayate to be the one to take the initiative. Hayate also gets really shy around the topic and generally thinks that a girl like Hinagiku wouldn't be interested in a guy like him. There's also the matter that he doesn't feel he can have a girlfriend due to Athena teaching him (very strictly) that he needed to be able to financially support the girl for life...his friends call him the God of Poverty, and there's also some guilt over how things ended with Athena. There has been much suspicion and a few nudges since it's pretty obvious to most everyone, the responses tend to be hilarious.
Given the seeming epidemic of Cannot Spit It Out and Oblivious to Love in this universe, this seems to apply to almost every pairing and for the unrequited ones they merely believed this is the case...except for Kotetsu who just cannot take a hint.
Umbrella of Togetherness - When Hayate has to spend a few days out of the mansion, and quickly loses all the money he was given to pay for a hotel, he winds up alone in the park without a jacket as it's snowing. After remarking that there won't be a cute girl to save him this time, Hinagiku appears behind him and shields him with her umbrella. When she invites him over to her place to warm up, the narration tastefully notes that it was the last time it snowed that winter.
Ayumu seems to be taking this one to heart, she was the first one to confess to Hayate, and he's even stated that they could be dating. But she seems more interested in making sure that Hinagiku is the one who finally wins out, and only seems to be in the competition at all to make sure Hina doesn't give up.
Athena sort of counts as this due to meeting him many years earlier, but Nishizawa still takes the title as she's known Hayate longer and was in the classic position of trying to get closer to him at school and get him to notice her despite his obliviousness.
Unsettling Gender Reveal - One butler falls in love with Hayate, who, at the moment is under a crossdressing curse (...). Although initially devastated when Hayate's cover is blown, he quickly comes around and tries to convince Hayate to travel with him to the Netherlands, where same-sex marriages are legal. (Cue Nagi's Megaton Kick.)
Luca, a pop star who first saw him after he was forced into a maid uniform (and had acted pretty freely around him, changing in front of him) gets this bad. Due to her busy schedule and debt she was under quite a bit of stress at the time when she sees him in the school bath, with some of his classmates with her. She ends up fainting, and is quite embarrassed about it for sometime afterwards, even messing up a performance.
Unusual Ears - Hinagiku gains donkey ears for a filler chapter following the trip to Athens.
Unwanted Harem - It's not so much that Hayate doesn't want the girls as he is too naive to understand their gestures of affection for him... which can be dangerous considering the occasionally (literal) military grade resources most of them can access when they throw a tantrum. (Nervous Laugh)
More like he has low self-esteem. Not to mention he sees half of them as kids, and because he's quite explicitly not a paedophile, can't even imagine them as love interests.
Anime Hayate shows an interest in those his age, Manga Hayate doesn't believe he can ever be anyone's boyfriend; and he has a lot of pent-up guilt over Athena.
Ironic since it seems like the older the character, the less mature they act. Most of the girls act thirteen-going-on-thirty, with cynicism on the red-line.
Wataru seems to have one of his own. He's just a lot more clued into it.
Uptown Girl - A little one-sided, at least at the start, as Nagi (the rich girl) has become infatuated with the extremely-poor Hayate after he saves her from kidnappers. She saves him from his (parents') debt, and he ends up serving her as a Battle Butler to pay her back. For her, it seems to be mostly just an excuse to keep him around.
The Unfought: In episode 28 of season 1, Hayate is in a combat butler tournament, facing off against foes who are obviously not Klaus and Tama. They give off an incredible Battle Aura, and the man does Clothing Damage to himself while powering up, causing his tie to fall into Hayate's hands, and handing him the win without having done anything, which he immediately points out.
Hilariously, this trope is enforced throughout the episode. Hayate either wins because his opponents are too scared of him, leave the arena for something, or he defeats them in one move without really causing any harm to them. He's a bit upset that he keeps winning by default or without really getting to put up much of a fight.
Hinagiku seems to be almost entirely unaware that she even has rivals for Hayate outside of Nishizawa. Likewise it's unclear how many people know for sure that Hinagiku even likes him that way (though most certainly suspect it) since Nishizawa never seems to tell anyone. This results in Nishizawa having several open rivalries over Hayate...none of whom know any of the others besides Nishizawa herself.
Ruka probably takes the cake due to taking an assertive interest early on, including stealing a kiss from Hayate, and despite making no secret of pursuing him managed to go completely unnoticed by everyone but Nishizawa until she flat-out tried to get Hayate to marry her in front of basically everyone.
One of the stranger cases has to be Kaoru-sensei and Ashibashi-sensei. Kaoru has had an obvious crush on Yukiji since they were in high school together. Ashibashi fell in love with Yukiji after she beat up a bunch of thugs trying to mug him while she was completely wasted. Kaoru hasn't been able to confess his feelings to Yukiji, but felt secure that no one else would be interested in her so he could take his time. Then he saw Ashibashi drive up in a fancy sports car and pick up Yukiji (who wasn't expecting him at all and only barely remembered Ashibashi in the first place due to being hammered). Now he doesn't even know who his mystery rival even is, and Ashibashi doesn't even know that he exists or that anyone else is pursuing Yukiji...all while she remains blissfully unaware that anyone is trying to win her heart at all much like her sister.
And now we have Kotetsu and Hayate's friend Souya from his old school, seen a grand total of twice after being in Chapter 1, after working to restore the seaside restaurant at the beach. Hayate was being surprisingly nice to Kotetsu for once when Souya walked up and interrupted them. Kotetsu took an instant dislike to Souya out of jealousy that Hayate apparently had a guy friend and afterward seemed to believe he was fighting Souya for Hayate based on his glaring and zeal to show up Souya at anything Hayate asked them to do. Souya seemed to take the unexpected competition well and they might just be friends by the end of it.
Was Too Hard on Him - When Hayate needs to assemble a team for Dungeon Crawling to get his job back he naturally goes to Hinagiku first as usual. Except she is still quite pissed at him for exploiting her fear of heights during the marathon race the day before to take them both out of the race so Nagi could win (which she didn't, thus why he had to do the dungeon crawl) and gives him a really hard time. After he bolts without even asking her for help, she starts to think she was too hard on him since it shouldn't be that big a deal and he seemed to be trying to tell her something important. Naturally she gets worried and goes after him.
This feel also proves crucial in Hina's Character Development since even she didn't know why he was so hard on him over it and why she felt so bothered by it. This led to the "Ice Age" where her interactions with him shifted to less playful and flirting and more giving him a hard time for minor mess ups only to regret it not long after. This went on until she realized she was having those jumbled feelings due to being in love with him and in massive denial over it and persisted until after the Greece Arc where it began to really taper off as she warmed back up to him.
Chapter 300. Not only did it see the return of Athena, who either appeared in a dream or broke into Hayate's bedroom. It also had Aika returning from Greece at last to set up a few possible plot points. Then things get weird when Hayate and Hinagiku are talking and a little girl who looks like Athena from the End of the World Arc appears out of nowhere and bumps into Hina. Then just to really make us all wonder what the hell was going on, Athena calls Hinagiku "mama".
Chapter 382 sgiws the moment Luca kisses Hayate.
Wham Line: From Episode 10 of Can't Take My Eyes Off You!, Hayate telling Nagi "I quit being your butler." Chapter 404 had a similar line where Hayate told Ruka that he doesn't wish to be Nagi's butler forever and will quit the day his debt is cleared and Nagi can live on her own. This time with heavy foreshadowing that said day is not all that far off.
Ultimately defied in another wham (counter-wham?) in chapter 510, where, even after paying off his debts, he decides to continue working for her.
Chapter 483 has a heart-to-heart between Hayate and Hinagiku. While most of the conversation is stuff the readers would know or has been heavily implied, we also got Hayate telling Hinagiku that if she were to confess to him, he'd be really happy and that being loved by someone as amazing as her would be a dream come true. It's followed afterward by Hayate explaining, while still believing this is a hypothetical situation of course, that even if Hinagiku did confess to him that he couldn't go out with her, not because he doesn't like her, but because of his massive debt. It certainly gave Hinagiku and the readers something to think about...
Chapter 553. After over 500 chapters, Hayate finally realizes Nagi has been in love with him the whole time and is left gobsmacked by this 'misunderstanding'.
While the series is a rare example of a series where "they won't" is a real possibility and it's up in the air if main heroines Nagi and Maria are indeed who the author intended the readers to root for, the early part of the series did toy with the possibility of Hayate/Nagi a bit more than others. Mostly on Nagi's end as Hayate never really displays that sort of interest...and is explicitly not a paedophile. It does a good job overall of making all of the girls very sympathetic and developing several quite well at the expense of having a single "main" couple to root for.
Later in the manga, after the Golden Week Arc, this starts to come into full force for Hayate/Hinagiku and starts to Ship Tease them mercilessly while still being as unclear as ever if it would ever happen. While the two have made some progress, their chapters are typically of the "two steps forward, one step back" where things don't quite reset but leave plenty of room for the other heroines to compete. However they have grown quite close over that time, even to the point of admitting things to each other that they wouldn't tell to other characters, which may hint at the author's (or at least the editors') intentions. That and the fact that around chapter 400~ or so the Hayate/Hinagiku Ship Tease gets more intense and happens almost like clockwork.
As of Chapter 483 this seems to have shifted into "they would, but..." after a rather heartfelt conversation. Given that Hayate had just turned down minor character Konoha's love confession after a surprise kiss from her earlier he was in a surprisingly open mood when Hinagiku approached him to ask him about it. When Hinagiku asked the critical question, what if it had been her that confessed her feelings to him instead, Hayate for once gave a serious and direct answer: he would be very happy if Hinagiku were to say that she loved him and he truly feels that being loved by someone as wonderful as her would be a dream come true. This leaves the current situation as, Hayate pretty much told Hinagiku that he likes her, but still doesn't believe she could actually fall for him, Hinagiku now knows that Hayate would return her feelings if she told him, but that she can't right now because Hayate couldn't go out with her even if she told him, not because he doesn't like her, but because of his massive debt. Now Hinagiku will be looking for ways to help get Hayate's debt payed off, and she certainly seems to believe that "they will" once he's debt free.
With This Ring - Takes a full swing at this trope in The End Of The World flashback arc. While he was a kid, Hayate worked hard and finally was able to buy a ring for Athena. Unfortunately, it's a ring for an adult, so their six-year-old forms can't wear them yet. Athena responds by offering Hayate a similar ring, and the vows and rings are exchanged and they promise to marry when they get older. Hayate then goes and gives the ring he got to his parents, who take and sell it to a pawn shop. Athena gets angry at Hayate when he returns later, presumably having seen what happened.
The ring is later seen by Yukiji, given how it's priced, it seems possible that the ring is a fake.
The ring that Athena kept a hold of returns to the story when the group makes a trip out to Athens during their Golden Week vacation. First it's admired, and then left out in the open, by her when she's seen Hayate again, not having known where he was for the intervening years. Then Hayate notices it and picks it up. She also gave the ring-box (empty) to Nagi, his current master before she dissapears at the end of the arc.
It's not seen when he gives it back, but Athena later shows it as proof that it is her when he's questioning his sight.
World of Snark - Due to knowing that they are characters in a manga/anime and the hilarious attempts to actually apply this knowledge, just about everyone makes sarcastic or witty remarks. Nagi and Hinagiku snark at the villains and weirdos quite often, the SC Rangers, Wataru, Sakuya, Ayumu, and even Isumi and Maria all make disparaging comments about the craziness around them. Hayate himself probably takes the cake, especially in the manga where he is a lot more cynical than he usually appears and has had exasperated reactions to damn near everything.
Wonder Child - Although altogether average kids, the Katsura sisters fall into this category. There's nothing inherently special about them, but their adopted parents were unable to have children of their own, so when Yukiji was looking for foster parents and chose her former teacher and his wife, they were probably thought of as this.
The Worf Effect - Hayate suffers from this quite a bit at a few points in the manga. It's actually rather unavoidable though as the cast is almost entirely made up of non-combatants. Some enemies are a total joke, some need to punt Hayate across the room to be taken a bit more seriously. Hell, Machina nearly killed him to set up the drama of the Greece Arc going into full swing, which would later be repeated by the arc Big Bad King Midas. To his credit, Hayate scared the former badly enough to make him want to use "That Technique" just by threatening to get back up and looking deadly serious and was able to defeat the latter even with his injuries.
Really, the only other characters that even could get this treatment are Hinagiku, Yukiji, named butlers (as most are just Red Shirts), and Isumi. Hinagiku gets her moment in the Butler Quest arc getting zapped by a demon-possessed Yukiji. Yukiji and Kotetsu share a moment with Hayate during the Mount Takao trip against an insanely huge and powerful grizzly bear. Isumi even gets one in the Greece Arc when her ultimate attack is defeated by Machina/Athena/Midas...whatever the heck the snake thing was. Hayate simply takes the brunt of it since he's established as the Iron Butt Monkey of the series.
Worf Had the Flu - There actually is usually a reason for Hayate losing fights or having a much harder time than he should. The primary reason is that he's actually a trained swordsman, though he lied about early on and limits himself to fighting unarmed which, could put him at a disadvantage. Also he apparently has access to an MG3 and plenty of skill with it even before the start of the series - if he brought that thing to every fight he could winjust by waving it around (one-handed no less). Aside from that the biggest contributing factor is probably that he doesn't want to fight in the first place leading to him putting up with way more than he'd have to simply because he doesn't fight back.
Workplace-Acquired Abilities - This is the explination given for many of Hayate's non-butler skills. Between the jobs he did for his father and the jobs he did to support himself since he was 8. His skills as a butler have a completely different origin.
Worthless Yellow Rocks - While it's not gold, when Hayate is told to spend three days away from the mansion because Nagi's embarrassed, he's given one million yen. Which he promply loses. It gets returned to the mansion and Maria counts it, stating that it's almost exactly what he was given for living expenses. Nagi passes by the table and asks what all the chump change is.
The characters, especially Maria and Nagi, have continually shown distain for the value of money. Such that it's a huge leap in Nagi's showing maturity when she's willing to give it up.
Nagi is well-versed in economics, and she says that even a single Yen is important. Not that she's ever seen a 1 Yen coin before. When Hayate shows her one, she thinks it's play money.
Wrong Genre Savvy - While the characters often seem to know they're in an anime/manga, they just as often think they're in an actual fighting series, not a parody.
Sakuya is aware she's in a comedy series, she just has the comedy style wrong.
Why Did You Make Me Hit You? - Played with in the 'End of the World Arc'. Hayate wants Athena to join his family outside the RG and she can't bring herself to ask him to risk himself to allow her to, they fight (lethally), and then Hayate unknowingly triggers her berserk button of her not having parents, to which she then 'slaps' him by ordering him to leave (so she doesn't kill him?), before she's able to break down, he does so, thinking he's failed her. Afterward she breaks down crying for having to resort to ordering him away to protect him. He does try to return to apologize, but finds he's unable to.
Yakuza - The cheerful Lampshade Hanging the show offers of this, as well as the over-the-top sugar-coating they give the activities of said very nice people to make it viewable to its younger audience, arguably makes it funnier to anyone old enough to know what they're really referring to.
Do note, however, that calling them "very nice people" was a form of censor on the anime due to its time slot. The manga outright calls them Yakuza and makes all of their actions perfectly clear.
Yaoi Fangirl - Izumi Segawa. "Sorry to bother you. Please don't mind me and continue."
Yaoi Guys - Parodied with Hayate and Kotetsu. Kotetsu tries to be the Seme to Hayate, who under other circumstances would fit the Uke stereotype. However, Hayate has made it very clear that he does not swing that way and, thus, does not want any of that. Kotetsucannot take a hint.
You Didn't Ask - After 88 chapters, Hayate reveals to the other girls that he's had a girlfriend in the past, and she's the reason that he's completely clueless about all the other girls all but throwing themselves at him, even the one who's actually confessed to him. Even later he reveals who this girl is, and everyone realizes that they know of her and one of them was actually seen as her best friend. The phrase is never actually spoken, but there are reaction shots with this being their expression.
You Must Be Cold - In the first episode/chapter Hayate gives his jacket to Nagi when she's freezing.
Subverted in chapter 262: Athena tells Hayate she's cold, and he offers her his jacket, completely oblivious to her subtext - she wants him to give her a cuddle. He catches on eventually.
Although not quite implied that it's because she's cold, Hinagiku is seen wearing a male's (possibly Hayate's) jacket as she runs from the beach where she's just played beach volleyball, so she's in a bikini.
You Must Be This Tall to Ride - Hayate's absurdly rich mistress has an entire amusement park that was given to her as an elaborate Kick the Dog—all the rides require a height she is as yet unable to reach...and may never grow into.
Younger Than They Look - Believe it or not, the butlers Nonohara, Himuro & Kotetsu are all under 19 years old! This is pretty shocking since Kotetsu looks like he's in his 30s yet is actally a teenager and is also Izumi's older twin brother!
Maria is 17 years old, but many are often mistaken that she looks older due to her maturity. By the way, DO NOT IN ANY CIRCUMSTANCES SAY SHE DOESN'T LOOK SEVENTEEN!. Just Don't! Say it again or you will suffer the consequences! You have been warned!
Your Favorite - Seems to be a special ability of Hayate's. If he makes food for someone he will almost certainly tailor it to the person he is making it for, and he repeatedly shows knowledge of the girls' likes and dislikes.
In Chapter 371 he is shopping with Chiharu and casually references that Ruka doesn't like carrots, asparagus, or bell peppers. He then decides to get some peaches since he knows Chiharu likes them. She's excited at first and then realizes she never told him that; he responds that he knows because she always looks so happy when she's eating them. He was also earlier shown to make a special batch of honey-lemon tea for Hinagiku every morning for when she got back from her jog, and was seen to actually ask her what kinds of food she likes and dislikes (she doesn't like pickled plums and sour stuff and likes curry and hamburgers). There is a reason a lot of characters picture him like a housewife.
You Wanna Get Sued? - Virtually every episode contains lines with bleep-censorship to avoid trademark infringement.
Nagi: Hayate still has three transformations left! Hayate: No, I'm not Fr** za.
In more extreme cases, characters will be actively shushed by other characters to achieve this. See the example on the trope page.
The official English manga translation 'whites-out' letters in words for the same reason - a visual bleep.
Also in the anime, some cases have the scene replaced by the large version of the usual visual censorship gag with writing "Showing this will be a copyright infringement" or something like that.
Although the manga, at least, is very inconsistent about whether or not a trademark reference gets censored: for example, Klaus' first response when Maria told him how Hayate rescued Nagi was, "What kind of Gundam is that?" and he then insisted it would somehow shame the Sanzenin to have a Gundam as a butler. But then there are several occasions of the term "Gun[blank]m."
Zettai Ryouiki - Nagi's qualifies as grade S. Try to find an episode or chapter where she DOESN'T wear it.
Sakuya's is pretty good too.
Well, her voice actor did voice Rin Tohsaka, THE epitome of Grade S Zettai Ryouiki, in Fate/stay night. As some people have said, the fact that Sakuya is voiced by Kana Ueda in the anime makes her ten times as hot as the manga version.