Q.E.D. (manga)
Q.E.D. is a mystery manga by Motohiro Katou in the same style as Detective Conan and Kindaichi's Case Files. Unlike those two, however, the main character Sou Touma does not stumble onto murders with absurd regularity. Instead, he encounters a variety of crimes ranging from murder to fraud. Also unlike his contemporaries (who either work alone or whose partners provide minimal assistance), he often works in tandem with his friend and potential love interest Kana, with him supplying the brain while she acts as brawn.
The manga is also notable for the fact that the characters visibly age, and that while Sou and Kana encounter many cases, they are apparently few and far between. As of book number 9, for example, a year has already passed (in book 3, Sou gives Kana a pearl necklace as a Christmas present. In book 9, the pair are invited to take part in a mystery game during Christmas).
Main characters
Sō Tōma (灯馬 想, Tōma Sō): The main character of the series, like similar boy detectives Shinichi Kudo and Hajime Kindaichi this 15-16 year old boy is a genius detective. Unlike the other two, however, Touma is not particularly interested in going out and finding wrongs to right. Rather, it is his erstwhile partner Kana who drags him into getting involved. An introvert, he seems to be well-known for his intelligence, but not particularly popular.
Sou is introduced when Kana Mizuhara rescues him from an irate customer at a video arcade. He then assists Kana's father in unmasking a murderer. Following that, he and Kana are often seen together, though she denies they are going out.
Sou's past is a mystery, and he appears to be a sort of Renaissance man in that he possesses a wide range of knowledge. What is known is that he was a student at the famous MIT in the United States, but dropped out for an unknown reason and came to join Kana's high school. While highly intelligent, Sou is often seen being amused by such simple things as snowflakes, suggesting he did not have an ordinary childhood.
Sou is also often the unfortunate recipient of Kana's violent tendencies, as he is often bopped on the head for reasons ranging from asking an embarrassing question in public to accidentally looking up her shorts. Despite this, and despite complaining whenever Kana drags him somewhere against his will, he does show concern for her and often takes her along whenever he goes out of town.
Besides being a genius, Sou is also quite wealthy and can speak in a number of languages including French. He is seen as having interest in archeology and biology.
Kana Mizuhara (水原 可奈 Mizuhara Kana): the second main character of the series, Kana is a spirited, tomboyish girl who excels in virtually every sport she attempts. She first encounters Sou when she rescues him from being attacked by a bully at a video arcade. She is warned by her close friend that Sou is a mystery (having apparently come to their high school after quitting MIT) and she should probably leave him be. Shortly thereafter, her friend learns her father was murdered, leading Kana to drag Sou along to support her. Her father, Detective Mizuhara, is the man in charge of the case and with Sou's help arrests the murderer.
Since then, the two have been nearly inseparable, in that Kana drags Sou almost wherever she goes. She categorically denies that the two are dating, but there have been many hints in the manga that she is slowly developing feelings for him (on one occasion, when she learns both of them have no plans for Christmas she attempts to ask him if he'd like to spend it with her, but is interrupted). The fact that she knows so little about his past bothers her greatly, and she often tries to find out more about him (going so far as to secretly follow him after school). What little she learns often either impresses her or makes her unhappy at how much Sou's been through.
Kana is a popular student, and she is often seen in a leadership role. She practices judo and kendo, the former skill often coming in handy when attempting to defend herself or Sou and apprehending suspects. She is also apparently infamous for her violent tendencies, showing no mercy to anyone who dares suggest there is something more to her and Sou than friendship.
Support characters
Detective Mizuhara (水原 警部): Kana's father. A gruff, unshaven police detective, he is initially outraged that a boy was sitting in his precious daughter's room. However, when said boy proved to be highly intelligent and of great use in unmasking a murderer, the detective developed a healthy respect for his abilities. Since then, he seems trust Sou a great deal as he often allows Kana to accompany him on trips unsupervised.
Loki (ロキ Roki): Real name Sid Green (シド・グリーン Sido Gurīn). An old friend of Sou from MIT, Rocky is like Sou a highly intelligent (though sometimes crude) individual. He and Sou are like brothers, him often teasing the younger boy. He, Sou and Kana have met on many cases. His nickname is named after Loki, the god of mischief from North mythology. Like his namesake, he enjoys riddles, pranks and games. While he and Kana get along fine, she objects to his smoking habit.
Eva Sukta (エバ・スクタ): Loki's partner and love interest. A dark-skinned Asian girl, she, Loki and Sou were friends at MIT. However when Sou and Loki were in direct competition Eva stole and destroyed Sou's thesis. Years later, Sou revealed he knew about it, but said nothing because he knew she did it because she loved Loki. While Loki was initially outraged, Sou calmed him and said he'd long since forgiven her. She makes occasionally appearances in the manga, often assisting Rocky.
Yu TOUMA: Sou's younger sister, Yu is highly intelligent in her own right. She is a polyglot. She first appeared in the manga to visit her big brother. Since then, she makes occasional visits but rather than help out her brilliant brother in solving cases she provides insight and backstory to Sou. She and Kana get along well together and Yu shares some of Sou's history with her, including a tragic incident in Sou's past.
Annie Craner (アニー・クレイナー): A young lawyer Sou befriended during his time in America, she was an important part of his life. She was shot after winning a difficult, emotionally charged case. Sou was a witness, and the event still haunted him when a killer began stalking and eliminating people involved in the case.
Sou and Kana
One of the major draws of the manga is the growing relationship between Sou and Kana. While for the first few books there is not much sign of anything other than friendship (Kana apparently being the first friend Sou has made since entering the school), in the 3rd book Kana imagines being given a pearl necklace by Sou. She laughs it off as absurd, but is surprised when he really does give her a necklace as a present. In the same book, she mistakenly believes Loki and Eva came to Japan to bring Sou back to the United States. She makes a mad dash for Narita airport, hoping to stop him. When she encounters Sou, she immediately bops him on the head and demands to know what he is doing there. When an understandably irate Sou replies that he was there to see them off, Kana is visibly relieved.
As the series progresses, it becomes clear that Kana does enjoy being around Sou (something that does not go unnoticed by her schoolmates). Her juniors in kendo, for example, believe Sou is Kana's boyfriend after meeting him and seeing how they act around each other. Their closeness is apparently well-known; after Kana sprains her wrist after a suspicious event in kendo one of her teammates informs Sou, who immediately rushes to the nurse's office. This show of concern prompts teasing from Kana's senior and friends.
While for the most part, it appears as though it is a one-sided affair (due to Sou being rather introverted), there have been occasions where he shows she is important to him. Following the above event in Kana's kendo class, Sou tracks down the culprit. He later admits that while he would normally not bother, he had a good reason for solving the case and finding the one responsible. It is implied that he was not willing to allow someone who hurt Kana get away.
In another case, Kana is attacked by someone wielding a baseball bat. While she quickly disarms him, he then pulls out a knife. When Sou arrives looking for her and sees the knife-wielding suspect, he quickly rushes towards them and attempts to pursue him even though he is nowhere near as athletic as Kana. Kana stops him and tells him it isn't like him to rush into things like that, prompting him to embarrassingly admit he agrees it isn't like him. Kana realises he ran towards them despite the danger because he was worried about her.