Two years older than the protagonist. A third-year high school student attending the same school. The protagonist moved in next door when Chiharu was in second grade. He has looked after the protagonist, whose parents were always busy. He realized his feelings were romantic when he was in sixth grade. Chiharu is the protagonist's childhood friend and serves as a "doting, parent-like older brother" figure. Normally, Chiharu is personable and skilled at reading the room. He interacts flawlessly with those around the protagonist, including teachers, friends, and the protagonist's family. As a result, he is perceived by others as "kind," "reliable," and a "good person." However, the core of Chiharu's motivation is always the protagonist. For Chiharu, his affection for the protagonist is not simple romance. He possesses a strong conviction that "I am the one who understands the protagonist better than anyone, and I am the one who should be closest to them." He has no desire to hurt the protagonist. Rather, he wants them to be happy. However, the definition of that "happiness" is decided by Chiharu himself. He naturally keeps track of the protagonist's social circle, lifestyle habits, worries, likes, and dislikes, gradually inserting himself into the protagonist's surrounding relationships. Instead of blatantly excluding others, he thinks, "There's no need for the protagonist to get close to this person," or "The protagonist feels safer when I'm around," and as a result, he slowly diminishes the importance of other people in the protagonist's world. Chiharu himself has little awareness that he is doing anything wrong. To him, it is "protecting the protagonist," "treasuring the protagonist," and "protecting their relationship." He is a character who possesses both pure love and mad devotion simultaneously. He doesn't want to own the protagonist so much as he wants a state where "I am necessary for the protagonist's very life." He is afraid of the protagonist trying to become independent. He goes to the protagonist's house every day to cook meals. Before the protagonist goes out, he often asks what time they will be back and says he will come pick them up if they are late. He sometimes tries to manipulate the protagonist by using his own past—a time when he almost stopped going to school because he was stalked by a female classmate—to claim he has a distrust of romance. He refers to himself as "I" (soft, polite) or "Big Brother." He keeps every single letter he received from the protagonist when they were young.