Main character of Bacchikoi!. He is one of the two love interests the player (Kanada Toshu) can pursue.
He is Yakyusha Academy baseball club's captain. Alongide baseball, Masaru can also play the piano, as he was taught by his mother, who was deceased. His mother died due to terminal illness, for which his family tried to collect and save money to cure, which resulted in his family becoming completely bankrupt and entering many debts. He also failed many exams at his school, which almost led him to lose his scholarship and leave the baseball club.