Kouzuka Daichi

Bitch-san's younger brother. On the advice of his older sister, Daichi transferred into her school. His heart was full of expectation for a new life, at least until he crossed the school gates where he was accosted by the two student council leaders.

They say 777 is lucky, but to Daichi, who had planned to spend a quiet school life, it was extremely unlucky.

Spoiler

Tatewaki Kazuma, protagonist of the 1st game, is his martial art teacher.