Yae and Takumi grew close and fell in love while in college, but after she graduated she got a steady job. He didn't, still hoping to pursue his dreams. He got by on short-term, part-time jobs, but, in the end, Yae ended up paying most of his expenses. They started arguing regularly. Yae tried to confront him about their issues once while he was drinking and he lashed out at her. After beating her he would cry and apologize, but it became a pattern that eventually drove her mad. Even though Yae always forgave him, inside she wanted to be set free from Takumi. She talked him into coming to Hinamizawa on a drive together, where she laced his drinks with sleeping pills and strangled him to death. The others had never seen Takumi awake because he'd been dead before they got there, and when they'd left Yae had ended up hiding the body in the closet with the blankets. When first confronted, she tells the others that she doesn't regret it, because she believed she had fought for her peaceful life and that it was all she could do.
Eventually, Takumi's spirit reveals that he had found a normal job and given up on his dreams to make Yae happy. This makes Yae realize what she did was a huge mistake and asks the others to leave her alone with Takumi's body for a while. "Mion" offers her a gun, for reasons between them, and leaves her behind. Although devastated by the truth and her mistake, she resolves to keep living and turns herself in as a form of penance.
