Birds of a Feather: Yukino and Hachiman, no matter how much they deny it. Both are sarcastic bookworms with a matching sense of humor. Both share their cynical view of the world, and, at the same time, feel the obligation to help those they encounter. Both have a truckload of painful social experience.
Two Girls and a Guy: The trope is played in a uncommon way because the guy is the protagonist. On the romance side of things, one girl is interested in the guy. The other girl's interest is somewhere between ambiguous and non-existent depending on who you ask. Although the guy finds both physically attractive, he doesn't want a relationship with either.
We Help the Helpless: Not to the fantastic extent of most examples, but their club mission is to offer a hand to anyone in need.
Hachiman is the story's main protagonist, an isolated, friendless boy who is pragmatic to a fault. His most prominent feature is his set of "dead fish-eyes". He firmly believes that "youth" is simply an illusion created by hypocrites, for hypocrites, born from the ashes of past failures. In this state of apparent corruption, he is coerced into joining the Service Club by his futures advisor in the hopes that exposing him to the world will change his personality, and ultimately make him a "better person".
Ambiguously Bi: Although he does indulge in Eating the Eye Candy when he blunders upon it (while getting knocked flat onto the floor as a female student is passing, for example), he seems more attracted to Totsuka than any of the girls.
Bad Liar: Not always, but when it comes to his romantic history he is. His difference from the usual practitioners is that he mixes lies with facts and tries to reinterpret them in a positive and heroic way. No one is fooled, including himself.
Brilliant, but Lazy: Clearly quite intelligent and observant but generally has to be dragged into acting by whatever request at hand or Shizuka.
Broken Pedestal: To Yukino surprisingly, much like how she was one to him. She considered their mutual belief in always telling the truth. and their dislike of false appearances to be the one thing that prevented them from completely hating each other. And when Hachiman does exactly that to preserve the Service Club when Yukino runs for Student Council President, their relationship starts to fall apart.
Butt Monkey: Both in a comedic sense and and in a serious one. He's generally on the receiving end of snark and physical punishment from Yukinoshita and Shizuka respectively. Though in other examples it's not as Played for Laughs, such as his acts of social suicide.
Byronic Hero: Is he intensely introspective? Yes. Is he cynical and jaded and has he experienced a bargain bin of a dark and troubled past bundled with regrets? Yes. Does he see his own values or passions as above everyone else's? Yes. Is he doggedly determined to follow his values and passions despite trampling over others? Yes. Is he especially physically attractive?...No - well, good enough.
Celibate Hero: Actively tries to avoid "Rom-Com" situations, and does not believe that he deserves love. Best shown when he rejects Yui's feelings for him because he believed they were driven by her guilt.
Chronic Hero Syndrome: Despite his outlook on society, if he sees someone in need, he will help them no matter the toll it takes on himself.
Covert Pervert: Never misses the chance to check up on girls (and Totsuka). Every time Yui approaches him, he notices her chest first and everything else later. Manages to appreciate being touched by Hiratsuka-sensei's breasts while she grabs him in Sumo grapple(for your info: hurts like hell). Derives sexual references out of thin air in the first 100 words of the very first chapter... well, you get the picture.
Dismotivation: fits Hachiman to a T. Among the usual reasons, like not wanting to be hurt again, he has an uncommon but somewhat logical argument.
Hachiman: "We only change to avoid the current situation. The true meaning of not running away is planting your feet firmly in the ground and doing the best you can with your present. Who's running away now? Why can't you just accept who you are and were?"
Don't You Dare Pity Me!: He welcomes hatred, rejection, isolation, and disgust. But the one thing he cannot accept is being pitied for what he himself chose to do.
Dude, Where's My Respect?: Members of the Service Club (plus Hayama) know that he willfully provides twisted solutions to club's cases, sometimes taking the heat in the process. Others just see a manipulative asshole.
Takes an interesting turn later on where Yukinoshita of all people starts giving him too much credit, and starts having doubts about her ability to resolve other's problems.
Heroic Self-Deprecation: A major part of his moral philosophy is that, as long as someone else is happy in the end, it is perfectly okay for himself to be hated or undergo suffering. The implication is that Hachiman thinks of himself as less than others.
This aspect of him is actually a major plot point later on, with people lampshading how he is a "monster of logic" that searches for hidden meanings behind people's personalities and actions without understanding the emotions that may have driven them.
Shizuka Hiratsuka: "Your eyes are like a rotten fish's".
Hachiman: "Do I look that much full of DHA? I must be pretty smart."
Last Name Basis: Prefers to be this with everyone, mostly because he does not see the point in using first names just to show how close you are with one another.
Logical Fallacies: Uses and abuses those to no end to justify his outlook on life in the arguments and essays. Gets called out on that repeatedly.
Loners Are Freaks: He purposely tries to avoid socializing as he finds small talk meaningless, and doesn't want to get hurt again, in the case of dating.
Loophole Abuse: In a sense. While he does technically solve many of the requests given to the service club, his methods don't really improve the people around him, which causes some frustration among both Shizuka and the other club members.
Misunderstood Loner with a Heart of Gold: Is definitely a good guy morally, however his methods, as well as his refusal to elaborate to other people his plans, cause his classmates to alienate him further.
My Sister Is Off Limits: Very protective of his sister, and really does not appreciate the fact Kawasaki's brother calls him big brother.
Hachiman (after remembering a rejected confession of the past): "For me these kinds of romantic developments don't happen in real life. In order to prevent a tragedy (read: rejection) from occurring I just have to be hated."
Not so Above It All: A major part of his character is the fact that even he isn't immune to his own cynical criticisms. And even despite his experiences there's hints that he just wants to experience high school like everyone else.
With Yukino and Hayato, but they also differ in many other ways which leads to the theme of the story.
Another example being his underclassmen Iroha, while being on two completely different ends on the social food chain, they have surprisingly similar personalities. This is lampshaded to the point where Hachiman considers her the second most rotten person he knows (The first obviously being himself).
Odd Friendship: While by no means friends, he and Tobe get along surprisingly well, Tobe being one of the few popular kids Hachiman actually tolerates.
In the novels, he's shown hanging out with both Totsuka(a popular tennis player) and Zaimokuza(a chuunibyou otaku).
Opposites Attract: May or may not have this kind of chemistry with Yukino. There is no denying that one of the main plot points of the series is how they interact with one another despite their contrary philosophies; whether or not there is romance involved has yet to be seen.
Though it must be noted that Hachiman admits that he finds her physically attractive, but claims that everything else is rotten.
Perpetual Frowner: His default expression, which isn't too surprisingly considering his outlook on life.
Poisonous Friend: Takes this role much of the time; he may be twisted but he cares enough about others to take the fall for others.
Refused The Call: Hachiman is adverse to joining the service club and leaving his self-imposed solitude. Good or bad, the call can make sure he doesn't graduate in only 3 years.
Rousseau Was Right: Is surprisingly enough a believer in this, as he shows when he quotes Sōseki Natsume
Hachiman (Quoting Natsume): “You seem to be under the impression that there is a special breed of bad humans. There is no such thing as a stereotype bad man in this world. Under normal conditions, everybody is more or less good, or, at least, ordinary. But tempt them, and they may suddenly change. That is what is so frightening about men. Don't trust anyone - that was what Natsume Soseki was trying to tell us. ”
Selective Obliviousness: Unlike other protagonists in the genre, Hachiman is very observant of the way people act around him. He simply picks and chooses what is necessary to acknowledge.
Serious Business: When Totsuka offers to trade emails with him, his reaction is a bit overboard.
Ship Tease: Mostly with Yui, and surprisingly enough Saika. At first there doesn't appear to be much with Yukino, but there are a lot of subtle hints as the story progresses. Then there are the moments he shares with Shizuka...
And in the later novels has quite a bit with his underclassman Iroha Isshiki, and surprisingly enough Kaori Orimoto, the girl he asked out in middle-school.
The Snark Knight: Hachiman is both defined by this trope and, in a way, also defies it:
Knight in Sour Armor: While he is antisocial and is pretty much disgusted by all human beings including himself, Hachiman also slips out strangely heroic actions, suggesting a part of him still wants to believe there is good in others, and himself.
Stepford Snarker: He snarks and speaks self-assuredly of himself in many instances, almost enjoying being a loner. Nevertheless, part of his ideas come from harsh social experience and a desire not to be hurt.
Token Evil Teammate: He often fills this role in order to get things done, such as finding and bringing Sagami back when she runs off from the school festival. He does get called out on his seemingly harsh treatment of people when he does this however, even though some of them understand the intentions he has.
What Is This Feeling?: Hachiman has twice, so far, wished to befriend Yukino. There is a good chance he hadn't wanted anyone specific to be his friend for years. However his feelings were promptly crushed - courtesy of Yukino.
Yukino is the leader of the Service Club, of which she is the sole member until Hachiman joins her. She is smart, beautiful, and is nicknamed the "Ice-cold Beauty" for her icy demeanor. She has a twisted sense of "noblesse oblige", and believes that it is the duty of the exceptional (in other words, herself) to help the "lost lambs" of the world. Her personality often leads her to be disgusted at the naivete of others, particularly Yui's, and she does not hesitate to show it.
A-Cup Angst: While she certainly isn't small, she doesn't react well when people compare hers with Yui, Yumiko, Shizuka or her sister Haruno.
Hachiman:"We only change to avoid the current situation. The true meaning of not running away is planting your feet firmly in the ground and doing the best you can with your present. Who's running away now? Why can't you just accept who you are and were?"
Yukino:"If that's so, then there would be no way to relieve concerns and no way to redeem one self would there?"
Berserk Button: Strangely enough, insulting her favorite mascot Pan-san.
Borrowed Catch Phrase: Yukino starts using Hachiman's catch phrase "source: me" or it's variants by episode 3.
Broken Pedestal: To Hachiman, who initially admired her for being a strong-willed person and for always telling the truth. This illusion breaks when he realizes that Yukino knew that he was the one her car ran over and pretended to have never met him during their first meeting, and as a result the two grow more distant towards each other.
And this is twisted back with Hachiman becoming one to Yukino, because she thought they both shared a common hatred of false pretenses, that dissolves when he tries to maintain the status quo much like Hayama's group does.
Brutal Honesty: It's one of her defining personality points, and also the reason Yui likes her so much. Though it is less about a need to be honest and more with the fact that she is a direct person by nature.
Childhood Friend: Of Hayato, or at least their parents know one another and they went to grade school with each other.
Catch Phrase: "I don't lie." Due to this catchphrase, it really hits Hachiman hard when he realizes she has lied to him before.
Chronic Hero Syndrome: Mostly a coincidentally positive consequence of her ambition of Utopia Justifies the Means. Yukino does not actively go out helping people, preferring them to come to her, making this a rather twisted sense of Noblesse Oblige.
Color Motif: Yukino tends to dress in quiet, subdued, black or white colors, which are occasionally accented with the formal purple.
Not so Above It All: Yukino, despite trying to be as perfect as it gets: she's easily coerced into doing things when accused of being afraid of something, lowers her shields around Service Club members(if ever so slightly), and can sincerely enjoy the sports festival(Hachiman spoiling the victory with his schemes notwithstanding). Not to mention her relationships with cats.
Opposites Attract: Inverted, maybe. Yukino says she doesn't like Hachiman, for one, because his ideals are opposite to hers.
Utopia Justifies the Means: This trope is downplayed. In her words she wants to change the world in order to avoid the downfalls of human nature. For example the tendency of the talented to suffer for their gifts. Her means of doing that involves bluntly criticizing people.
Will Not Tell a Lie: Is known for telling the truth no matter how harsh it might be, though she is capable of half truths and clever semantics. However, Hachiman finds out Yukino did lie when she claimed she didn't know him before their initial meeting. This puts quite a bit of strain on their relationship.
Yui is a cheerful, outgoing girl who becomes the Service Club's first "customer", asking them to help her bake cookies for "a certain someone". Her problems lie not with her personality, but with her inability to deal with issues by herself. She believes that talent is inborn, and often aspired to be like others until Yukino changed her way of thinking. Following her experience with the Service Club, Yui begins to attend Service Club sessions after school as well, despite Yukino's objections early on.
Ambiguously Bi: When asked by Yukino's big sister what she thinks of Yukino, Yui can't help but talk like a lovestruck highschool girl as she explains. This is while she's already hinted to have romantic feelings for Hachiman. Considering that Hachiman himself is also Ambiguously Bi...
Animal Motifs: Her choice of pet and overall personality likens her to dog.
Bokukko: In the anime she's greeted Hachiman with slang usually used by guys and will sometimes speak like one (using "ore" instead of "watashi/atashi") around Yukinon and Hachiman, though she has more of a Plucky Girl persona than that of a traditional Tomboy's.
Cannot Spit It Out: It becomes a little obvious that she begins to like Hachiman, but never states her feelings to him.
Clingy Jealous Girl: While it doesn't show up much, she doesn't seem to like it if another girl expresses interest or even just gets uncomfortably close to Hachiman, such as the girl who wanted help with the athletic festival in episode 13. She also gets a little upset when Hachiman shows a lot of interest in going to a maid cafe in episode 5 with Zaimokuza.
Color Motif: Yui is typically dressed in bright, feminine colors and, notably, her hair is a warm peach.
Cuddle Bug: Yukino is her favorite person to cuddle with.
First Name Basis: It doesn't take long for her to refer to most people by their first names, regardless of how well she knows them.
Foil: Yui represents what Hachiman and Yukino are not: expressive, warm, and inviting, but also naive, innocent, and a bit idealistic.
She seems to serve as this to her clique. Along with Hayama she's more insightful than her peers in noting the politics of the class. However, she struggles to rectify many of the conflicts due to her niceness.
The Four Loves: Eros is arguably a prime motivator for her behaviour concerning Hachiman.
I Just Want to Have Friends: A motivator for her relationship with Yukino and maybe Hachiman even. Although it depends on how the viewer sees her relationship with Yumiko's clique.
Lethal Chef: Can't cook to save her life. Yoshiteru passes out after eating a little bit of food she made in the OVA. Hachiman then forces himself to eat the rest of it, and though Yui is touched by that, he really did it because he didn't want Saika to have to eat it and suffer the same consequences.
Nice Girl: Freely interacts with Yumiko's clique as well as the more independent (or lonely) Service Club without any problems
The Nicknamer: Strictly refers to Hachiman as "Hikki", and Yukino as "Yukinon".
Hayato is a central figure in class 2F and the ace of the football club. He is extremely kind to other people, including Hachiman, and often offers his help to others. However, he claims that he can never forge a good relationship with Hachiman. He thinks that Yukino is close to Hachiman, and believes that this is due to Hachiman's twisted personality. He seemingly understands Hachiman's acts of social suicide to protect everyone.
Academic Athlete: Turns out he's not only the soccer ace but number two overall in their high school.
Foil: He's Hachiman's perfect opposite; popular, sociable, and nice (though not without his faults). Both ultimately have good intentions, but use different methods. Nevertheless, he has a mostly amicable relationship with him.
Hidden Depths: Initially seems like an overly nice but somewhat oblivious popular guy, but he's far more perceptive of Yukino and Hachiman's methods than most others
Nice Guy: Definitely a nice person, however he prefers to maintain his reputation while doing so.
However, he himself claims that he is not one to Hachiman on several occasions, saying that Hachiman is simply forcing that perception onto him.
Not So Different: Heavily implied to be the case with Hachiman, with most of their conflicts with each other coming from Hayama's sympathy with him and Hachiman's hatred of what he considers pity. And they apparently have a mutual understanding in regards to romance.
Hayama: “So basically, you’ve never really actually liked someone, huh? ...Both you and me.”
Status Quo Is God: A stern believer in this, he would much rather have relationships stay the way they are rather than resolve an issue that could potentially harm his friendships.
Yumiko is a popular girl from class 2F with a pompous personality. She is the main female figure in Hayato's clique. Due to her popularity, she has no trouble making friends and thus has little to no understanding towards people who have social troubles. She brushes off anything she doesn't understand as "making no sense".
Dumb Blonde: Downplayed. She's not outright stupid, but she's not the sharpest spoon in the shed either.
Foil: To Yukino; both characters are stubborn, somewhat haughty popular/former popular girls who are good friends with Yui. The major difference is probably the harsh social experience that Yukino faced to fuel her beliefs.
Saika is a member of the tennis club who has a feminine appearance, but prefers others to not mistake his gender. He is called "The Prince" by his female classmates. On their first meeting, Saika asks help from Hachiman to join the tennis club, which was brushed off by Yukino. Saika then asked the service club to help him improve his tennis skills. He eventually became one of the few people in class 2F who would talk to Hachiman, and often hangs out with Hachiman.
Ambiguously Gay: The amount of affection he shows to Hachiman may raise a few eyebrows.
Saki is Hachiman's classmate who seems like a delinquent, but wants to make friends deep down. She cares deeply for her brother as she hid her name and age to work in night-shift part-time jobs in order to pay school fees and reduce her family's load.
Big Sister Instinct: Hachiman commented on her rare smile. The cause of her once in Hachiman's lifetime smile was her brother. Plus if Hachiman so much as discomforts her brother, she usually glares at him.
Ice Queen: The disposition she typically carries: distant, indifferent and callous.
Japanese Delinquent: With her disregard for proper dress code, tough attitude and loner status, Saki has a few typical delinquent traits.
Jerk with a Heart of Gold: She's rather cold, but she also cares very much for her family and tries her best not to burden them.
Not So Different: She and Hachiman are both isolated despite sharing different beliefs (while Saki is diligent, Hachiman believes that "to work is to lose"), and care similarly for their siblings.
Rapunzel Hair: About thigh-length, which makes it even more impressive how she manages to put it up in a bun at work.
Shizuka is Hachiman's teacher, a language teacher who serves as his futures advisor/counselor. She is aware of Hachiman's supposed "problems", and takes steps to ensure he is freed from them, her first move being to force him into joining the Service Club. However, she appears to have some quirks of her own: she is a young smoker, she is very sensitive about her age, and she is often prone to quoting or copying scenes from popular shounen manga. She also never remembers to knock before entering the Service Club's classroom, much to Yukino's chagrin.
Berserk Button: Mentioning her age or single status will either result in pain (in Hachiman's case) or just make her depressed.
Christmas Cake: It is mentioned that she is somewhere around her thirties, and several characters pray for someone to marry her already. In the OVA Hachiman states that if this takes too long, he'll have to be the one to do it.
Corporal Punishment: Shizuka has used it as a threat to keep Hachiman in line. The only times she has actually hit him, however, was simply because he pushed her Berserk Button.
Death Glare: Used one on Komachi in the OVA when the latter claims that none of the three contestants in wedding dresses won. She was about to claim herself as the winner, until Shizuka does a prolonged glare at her, scaring her into declaring the latter as the winner.
Got Volunteered: She likes to do this to Hachiman a lot. In the OVA she also ended up getting volunteered to do a special article on marriage, but laments to the other characters that she doesn't have enough experience in those aspects to do it. Unfortunately none of the other students do either, as they're a little too young to be thinking about married life.
Not So Different: Despite her desire to improve the personalities of the service club members, she seems to have some of her own interpersonal problems which parallel theirs(such as their mutual lack of love life).
Komachi is Hachiman's younger sister who, different from her brother, is cheerful and lively, and is a member of the student council in her school. She understands that her brother has a corrupted personality but still cares for and relies on him regardless.
Foil: Besides being the opposite of her brother, she's also one for Haruno. While both characters encourage their respective siblings in various ways, the motivations are slightly more ambiguous in Haruno's case.
Genki Girl: She tends to be a bit excited about things, especially when Hachiman is around.
Genre Savvy: Interestingly she's considered the "expert" on marriage in the OVA. Though Yukino did claim the former has experience in taking care of a deadweight, referring to Hachiman. And for the most part her answers do seem to match what they were expecting on what to write about regarding marriage for an article.
Yoshiteru is a student from class 2C who suffers from adolescent delusions. He sees Hachiman as a friend after being paired up with him during physical education lessons. While he is annoying, he has a group of otaku friends he's on good terms with. He aims to be a light novel writer.
Expy: Think Kouta Hirano if he weren't in a zombie apocalypse, right down to the same voice actor.
The Friend Nobody Likes: One of the few characters who weirds out the Service Club more than Hachiman usually does. Nevertheless, Hachiman ends up hanging out and relying on him on a few occasions.
Large Ham: All the time. Seems kind of par for the course when you're being voiced by Nobuyuki Hiyama.
Nice Guy: Despite his hamminess and delusions, he´s a pretty good guy.
Not So Different: Hachiman notes to himself that Zaimokuza's behavior isn't that far from his own in middle school. Both characters are loners who seem to revel in their eccentricities but while Zaimokuza seems to be happy in his delusions, Hachiman comforts himself through his cynical lens of reality.
Haruno is Yukino's elder sister who is even more outstanding than Yukino. However, unlike Yukino, she shows a good attitude towards other people, even if she has to lie about her true feelings most of the time. While Yukino holds strong animosity towards her, Haruno sees her sister who's constantly trying to overtake her as cute.
The Ace: Intelligent, heir to the family business, a brilliant musician and conductor, extremely beautiful and a social butterfly. The hurdle she leaves for Yukino is very high.