Leon Kuwata was a Half-Blood wizard that was born on the 3rd of January 1971 and started attending Hogwarts on the 1st of September 1982, being sorted into Gryffindor House.
He had an Ash wand with a Dragon Heartstring core.
His Patronus was non-corporeal.
His favorite subject was Flying and his least favorite subject was Defense Against the Dark Arts.
He was a member of the Frog Choir.
Leon is a passionate, hot-blooded young teenager. He often slacked off from studying and quidditch practice; however, his quidditch skills were never diminished due to his natural talent. In fact, he hated to practice, seeing no point or enjoyment in it because he was already so talented. Due to his natural physical talent, he considered even very difficult and unusual feats easy and had some trouble empathizing with people who lacked such talent, as he didn't fully realize how hard the bet he made with Kanon really was.
Despite his talent, Leon claimed he strongly hated quidditch and was very determined to switch over to the Frog Choir. He had a tendency to complain about the several things he found uncool and gross about quidditch, often without any prompting from others. He was quite arrogant, often talking about his popularity and dreams of being even more famous, considering himself a 'future superstar'. However, while hanging out with his best friend Makoto, he implied he wasn't actually very good at being a musician, and the reason he wanted to become one is to win a heart of a girl he happened to meet during his first year. He claimed that being popular is the whole point of being a musician, and once briefly thought about being an actor instead if that's what Sayaka is more into, generally appearing a bit confused about his own motivations and feelings for the matter. Furthermore, he was quite bitter about how people constantly forced him to play quidditch and follow the sport's traditions due to his natural talent, with his completely new goal and look appearing to be at least partially a form of rebellion.
However, in reality, Leon grew to miss quidditch after not playing for a while, since he used to do it every day since he was young and it actually made him feel good. He reluctantly admitted this to Makoto once while hanging out, as he needed someone else along with him to properly play. With all his talk about hating quidditch, he was embarrassed to admit how he really felt and accused quidditch of brainwashing him. He considered returning to the Gryffindor team, though he still absolutely hated the idea of practicing. Right before his death, he decided he would both play quidditch and sing, to become 'the ex-quidditch star who's a totally famous singer now' later in life. He liked the idea of an all-new approach that is just for him, showing that he just disliked repetitiveness and other people deciding things for him.
Leon was also strongly interested in girls and bragged about his great success with women to Makoto, asking him if he was jealous. While it was left ambiguous how truthful his claims were, it was confirmed by Hagakure after he graduated that he was indeed a 'player' with a new girl with him every few days. He was always flirting with girls and he was single-mindedly focused on studying "the secret of success with the ladies". He appeared quite shallow, as he often only talked about how hot girls are, but he has also mentioned he's into pure-hearted girls and he was grossed out by Hifumi's very perverted behavior, thinking it goes way too far.
By his professors, Leon is described as an optimist who wants to get better at everything he does. However, during the killing game, Leon was shown to be easily intimidated due to the intense situation, such as when Makoto spent time with him for the first time and he thought it was a trap to kill him, or during the investigation of Sayaka's murder when he asked and found out who Sakura Ogami is. When he became nervous or intimidated, Leon tended to smile awkwardly, often the right corner of his mouth stretching farther. He could also come across as easily offended and agitated; for example, when asked how he managed to style his hair, he immediately became annoyed, automatically accusing Makoto of making fun of it and saying he should shave his hair like his father made him do. He also instantly became angry and snapped at Makoto for not knowing what to talk about, and he often had quite intense expressions. It has also been shown that whenever he's upset or depressed, Leon liked to take naps. According to his friends, Leon can't stand the heat and hot weather. Right before his death, Leon showed a more patient and kind side, as he couldn't help but sympathize and worry about his younger cousin Kanon despite her obsessively being in love with him, with him wondering multiple times that's he's probably being too nice and once commented that it's no wonder Kanon liked him so much with how nice he was.