Tsumuhana Isuzu

Isuzu lives close to Hiroshi. She is tomboyish and extremely affectionate towards Hiroshi, sometimes to his dismay. She had an older brother named Issei, who attended university before succumbing to his predatory instincts and attacking Hiroshi. He was killed by Nemuru. She herself starts to submit and attacks Hiroshi, but manages to stop herself and is spared her brother's fate.