Awesome Ego: Escanor is so arrogant, he demands the Vampire King apologize for even existing in Escanor's world. Considering he can back it all up with his immense power, the fanbase loves him for it.
Base Breaker: Meliodas. Some people love, but others are often annoyed with his perverted behavior and how he rarely gets called out for it. Some people even refuse to watch the series because of this.
Crazy Awesome: While not nearly as much as the mangaka's previous Kongoh Bancho as of yet. The world is filled with warriors capable of causing the ground to shatter beneath them, even a Mook can easily cut down an entire forest with ease. Ban and Melidolas for example destroy Baste Prison because of their over-enthusiastic greeting.
Designated Hero: Meliodas, because of his tendency to grope girls. Well, one specific girl, anyway.
Helbram is quite favored, having placed in ninth place of a popularity poll.
Oslo is surprisingly popular for a bit character, having even made it into sixth place of the poll himself.
Escanor was eagerly awaited to make an appearance in the manga proper. When he finally did, the fandom exploded.
Fan-Preferred Couple: Some argue that Jericho deserves a break for all the trouble that she goes through for Ban and have her love rewarded by the guy, despite Ban and practically every other character having already said that he will only have eyes for Elaine. The number of times that Jericho has fumed with frustration every time she hears from Ban's mouth that he will do anything for Elaine counts as a few blows to her self-esteem since she would like it if Ban spoke that way about her too. Some fans want her to "win" even more after she successfully kept both Ban AND Elaine alive while running away from two of the Ten Commandments, even unknowingly leading them to their demise by having them run into Escanor. After the danger has passed, she even accepts Elaine as a friend despite the revived fairy trying to kill her before; providing her the speech necessary to snap Elaine out of her temporary madness. Since he's the embodiment of "greed", couldn't Ban have both Elaine AND Jericho, thus making both girls happy?
Foe Yay: Ban and Jericho. In their first meeting he strips her (yes, he wanted the clothes but it was obvious they wouldn't fit him) and, in the second, she stabs him saying "I'll crave my name on your heart" and paints her lips with his blood.
King has a brief moment with Ban in the Capital of the Dead Arc when he stabs Ban with Chastiefol while he was leaning on the spear with a flirtatious demeanor.
Harsher in Hindsight: In the second High School A.U. spinoff, there's a little skit which involves Gowther and Guila who're a student and a member of the school disciplinary committee respectively. Basically, the skit involves Gowther briefly brainwashing Guila's little brother Zeal in order to bypass her. The whole thing is played for laughs considering the nature of the spinoff. Come some certain chapters in the manga proper though, this skit doesn't seem as hilarious as it was before.
Ho Yay: With Threader, a guy who appears to be a badassStraight Gay, and Gowther, an extremely effeminate looking guy that could easily be mistaken for a girl. The conclusion of their battle in the Liones capital pretty much looks like something that could fit in a romantic comedy.
Ban and Meliodas. They were ecstatic to see each other again and Ban has the same lack of sense of personal space with Meliodas as with Elaine. In chapter 87 he literally said "I love ya, cap'n" and he obviously doesn't want to kill Meliodas despite he is willing to do so for get Elaine back.
Internet Backdraft: Chapter 79 opens with a picture of Meliodas sticking his hand under the princess's skirt. Some English-speaking fans did not like that.
Dreyfus. Sure, he murdered his own brother and blamed the Sins, but his obvious remorse and love for his son (and he thinks for a while said son was killed by his former best friend who now has become evil) make him this trope. Later it's revealed that he allowed himself to be possessed by one of the Ten Commandments to spare his best friend from being taken over.
Jericho. An Attention WhoreGlory Hound who simply can't catch a break. Her brother thinks she shouldn't be a Holy Knight because she is a woman. Her friend Guila joins the Sins and Jericho doesn't understand why. And finally, the power that was supposed to prove her brother wrong turns her into a horrible monster that almost killed him. She later loses the "Jerk" part after Character Development but steps into The Woobie territory when time and again she's reminded by Ban and others that his love for Elaine is so strong that she will never have a chance in hell at winning the guy's heart. Despite this, she still keeps trying to get him to notice her, even if it's just a little.
Les Yay: In the anime, Guila and Jericho have their moments, particularly in the first-season finale where Guila cheerfully announces that The Power of Love saved her from being turned into a monster like the other New Generation knights. Jericho thinks Guila is referring to her... and then looks incredibly jealous when Guila gestures to Gowther as the object of her affections.
Memetic Mutation: Using the Dark Souls often quoted phrase "Praise the Sin!" in regards to Escanor who has sun based powers. It's especially used when he's in his terrifyingly overpowered muscular day form and about to pretty much completely rekt those foolish enough to face him.
Memetic Loser: Griamor (the Holy Knight that makes barriers) just can not catch a break when it comes to who he is up against. The fact that he continues to fail at protecting the Liones princesses, and that his father, Dreyfus, turns out to be Evil All Along through what appears to be demon possession, doesn't help.
Golgius stabbing a man he forced to poison Meliodas to save his daughter. Luckily the man survived.
Helbram attacking the village and putting civilians in danger. His justification? "We need to make the Sins the villains for us being the heroes". Prior to that he said that his dead subordinates (who were giving him power) weren't a big deal because We Have Reserves. No wonder why Guila put a Heel–Face Turn at the end of the chapter.
Squick: Some find some of the relationships presented in the manga to be rather squicky. While opinions differ, a common thing that is often brought up among the relationships is how they consist of characters whose appearances make them look vastly different in age.
Some find Meliodas constant fondling of and general Lovable Sex Maniac antics towards Elizabeth to be rather squicky especially considering that he receives little to no reprimand for his actions from her and instead has Elizabeth slowly fall in love with him. Meliodas being Really 700 Years Old but having the body of a kid is sometimes added to the squicked out factor for some.
Some find Ban and Elaine's relationship to be rather squicky as he is a grown man and she has a body of a child. This disregards the fact that Elaine is actually a fairy and Really 700 Years Old, making Ban, a human, the younger of the two. Ban looking and acting like what could be interpreted as a lustful pedophile around Elaine in some scenes however doesn't help much.
Their reunion in Chapter 142 is sweet and they even kiss. Too bad Elaine was revived with dark magic and Ban was bleeding profusely from the mouth. The fact that they continue to make out with one another, despite Jericho being three feet away from them, counts as a Kick the Dog moment to her and Jericho's fans.
When the past relationship of King and Diane is revealed in King's backstory, some found it to be rather squicky and looking like Wife Husbandry due to the fact that he's technically older than her, and that she has the appearance and the personality of a very young child. This is a bit of a contrast compared to the case with King's sister Elaine as the fact that King is being also presented as a child due to his fairy form is disregarded. Furthering the contrast abit is that King's present relationship with Diane is found by some to be okay even though it is technically a complete reversal of their past with him being a child due to his agelessness and her being an older looking woman, a thing that also technically happens to be the gender reversal of Elaine and Ban's case.
While her true age hasn't been revealed yet, some find Vivian's obsession with Gilthunder to be squicky especially considering that she's been in love with him since he was a kid, and that she had taken him and Margaret hostage to prevent them from revealing the frameup of the Sins.
They Changed It, Now It Sucks: The reaction to certain changes made for the anime adaptation which involve cutting out a number of things from the source manga such as characters, foreshadowing, and even whole entire events. To name two notable ones which are a Chekhov's Gunman and Chekhov's Gun respectively, Oslo and the pendant that Veronica gives to Elizabeth before the Byzel Fighting Festival. The two do later appear in the anime during the parts wherein they actually become relevant in the story however due to the cutting out of their initial introduction, they come off as looking a bit more like sudden convenient plot device than anything else. This is somewhat more in the case of Oslo whose sudden appearance in the anime comes as looking like an Ass Pull.
Unpopular Popular Character: In the series, King is an extremely unlucky Butt Monkey who isn't even liked by his former fairy subjects. According to the first character popularity poll however, he's the most popular character overshadowing even the main character Meliodas. In postcard votes submitted by fans alone, he's in fourth place but combined with online votes, he's the most popular character by landslide with nearly four times the votes Ban in second place has.
When Gowther revealed his true form, many were confused whether Gowther was a man or a woman due to his rather effeminate features. Some are still confused. Since he was originally a doll, he technically didn't have a gender at first.
When Merlin finally revealed herself in the present, there has been some confusion over what gender she is. Most of it comes from her first full body reveal which despite presenting Merlin with her rather StripperifficMs. Fanservice outfit, her breasts aren't that pronouncedly drawn big. Fortunately Chapter 84 did a better job in, ah, detailing her (complete with some Gainaxing), making her being a woman much more clearer.
Simon who at least one person asked about his gender according to the Q&A in the first Fanbook. The answer is that he's a boy with a girly face.
Hawk might be seen as female due to his eyelashes, usually being the only one offended at Meliodas groping Elizabeth, and Crossdressing Voices.
Gloxinia a.k.a. Octololi of the Ten Commandments. Due to appearance and use of feminine Japanese Pronouns, alot of people assumed for the longest time this character was a girl. Then his actual gender is revealed along with the fact that he's actually a fairy.
The Woobie: In this manga most of the cast need a hug...
Ban tragically lost Elaine, the first person to actually acknowledge him, and it has been his personal quest to revive her. This has driven him so much so that Ban was beside himself when he was offered the chance to revive her if he would kill Meliodas, his best friend and the only other person Ban cares about.
Due to incidents beyond his control, King has suffered and lost a great deal. These include among things, King's best friend going mad to a point that King had no other choice but to Mercy Kill him THREE times, and the lost of the original Fairy King's forest along with the life of his sister. Worse yet, he is constantly reminded and blamed for all of these tragedies even when he was otherwise indisposed to prevent them.
Gilthunder. He lost his father at a very young age and for years had to remain silent about the identity of the murderers (one of them being his own uncle), while everybody blamed his dear mentor and said mentor's comrades. All of this because a Yandere threatened him and his girlfriend with death and sent monsters to monitor each of his steps.And he never complains or shows his suffering.