Mitsuki's step brother. He is a caring stepbrother despite having just met her stepsister. He constantly asked if Mitsuki was facing any trouble when she started acting weirdly.

Being the male main character in the show, he is the only one of the 3 main character who had not performed any sexual act or made lewd advances. He had however accidentally been seen naked by his step-sister once in the shower when his step-sister opened the spoiled bathroom lock from the outside. He is however the most sane main character in the show.