Len Tsukimori
Horoscope: Taurus
Family: Mother, Father, Paternal Grandmother, and Maternal Grandfather
School: Seiso Academy
Grade: Second Year, Music Department, Class A (2-A)
Instrument: Violin
Seiyuu/Voice Actor: Kishou Taniyama
First Anime Appearance: Episode 1
First Manga Appearance: Volume 1, Chapter 1
Len comes from serious musical stock—his mother Misa Hamai is a renowned pianist, his father's an accomplished violinist, and basically everyone in his family does music professionally. He's a child prodigy himself, which means his talent gets taken as a given by most people around him.
He's the type who comes across as cold and dismissive. Quiet, a bit surly, and contemptuous toward just about everyone, including his admirers (whom he typically ignores). Before meeting Kahoko, he didn't really believe music could be enjoyable—it was just something he was good at. But spending time with her changed that. Slowly, he started actually enjoying music, and his playing shifted because of her influence.
As for Kahoko specifically, he comes off harsh at first, even offering her pointers on violin technique and stance. The harsh exterior hides genuine concern though—something Kahoko and others eventually pick up on. As the series goes on, his feelings for her become clearer, and his whole personality starts to soften. His own mother noticed the shift and knew right away that Kahoko was the cause.
On top of violin, he can play piano too, likely picked up from growing up around his mother's world.
He's got solid academics too—English is his best subject, and he's apparently pretty competent in German as well.
Content compiled by AnimeList.moe from publicly available sources.