Makoto Isshiki is Yuuta Togashi's classmate. He has tanned skin, short dark hair (later shaved off), and indigo or grey eyes. He typically wears the school uniform: a long black jacket with white accents, a red and white tie, and brown shoes.

Personality-wise, Makoto is friendly and sociable, immediately befriending Yuuta on their first day. He frequently creates profiles of female classmates and actively seeks their attention, leading to repeated disciplinary warnings. His primary motivation is romantic pursuit; he joins the Light Music Club to attract girls with an electric guitar he plays poorly. This focus shifts when he develops genuine feelings for upperclassman Kumin Tsuyuri after she affectionately pats his head.

In junior high, Makoto disliked his baseball crew cut for making him look like an elementary schooler. He harbors concerns about premature baldness, stemming from his father's experience of losing hair at thirty-five, believing he will bald before twenty. A notable incident involves him conducting a "cutest girl in class" poll, resulting in him shaving his head completely as self-punishment.

Throughout the series, his role evolves from supportive friend to comic relief. In the first season, he perceptively encourages Yuuta to confess to Rikka Takanashi. His earnest, though awkward, romantic pursuit of Kumin becomes a recurring focus. By the second season, his appearances decrease, often serving as a source of lighthearted moments.

His key relationships are his bond with classmate and confidant Yuuta Togashi, and his persistent admiration for Kumin Tsuyuri, whose calm and nurturing nature contrasts with his impulsive tendencies. His family background is only referenced regarding paternal hair loss concerns.