Seitaro Higuchi is a university student who claims to be a tengu, a type of supernatural being from Japanese folklore. He has a large chin and black hair tied back in a ponytail, and is frequently seen wearing a green yukata. His personality is free-spirited and self-involved, with a tendency to do whatever suits his fancy. He often looks for different ways to make money and has a noted liking for all kinds of smoking, from pipes to cigarettes. He maintains a relaxed attitude, often smiling and offering words to others, while also displaying a sense of melancholy and wisdom in his interactions. He first meets the central female character at a quiet bar in the Shijo Kiya area at the beginning of a night. After she punches another patron, Tōdō-san, for making an advance on her, Higuchi and his companion Hanuki-san express their admiration for her actions. They invite her to join them in gate-crashing strangers' parties, which she agrees to do. During these events, Higuchi performs tricks to entertain groups, though they do not always receive a warm reception. He also finds a pair of black pants that he claims belong to a loan shark named Ri Haku and puts them on. In a related series, he is a student at the same university but has failed many main classes multiple times. Some know him as "the master" due to his perceived adulthood and wisdom, particularly concerning social and human relations. He is involved in a "proxy proxy war" with another character and is deduced from certain scenes to smoke weed. He has a free relationship with a girl from his generation who has already graduated from college. In one scene, he discusses finishing a book that had taken him a long time to read and appears emotionally affected by it. He also gives advice to another character about accepting themselves. He is present during a drinking contest on a three-story ferry where the central female character challenges Ri Haku.