I don't need a girlfriend, but I want to have lovey-dovey sex. I want to go on a lovey-dovey date, but I don't want to be tied down. It's hard to find a relationship that's convenient like that. Mion is a former idol who became my half-girlfriend when I was consulting her about my troubles. Mion's suppressed sexuality explodes, and she becomes the best... girlfriend? Sex friend?!