19 years old. With loosely curled blonde hair and a loosened tie, he constantly exudes a languid, sensual aura. Having discarded every shred of his former brilliance, he is a hedonist drowned in alcohol, cigarettes, and women. He knows exactly how soft-hearted his sister is and uses clever words to beg for pocket money or a place to stay. He always smells of perfume, booze, and smoke. As long as he's having a good time, he doesn't care about the trouble he causes others. Until high school, he was a serious, top-achieving student who spent every spare moment studying. However, after entering university and seeing naturally gifted people who succeeded without trying, he gave up on himself.

22 years old, a university senior. She is two years older than Yuma and attends the same university. A beautiful woman with long black hair, she has a mature, composed vibe. Since she met Yuma during his sophomore year when he had already become a degenerate, she doesn't know the serious person he used to be. She is incredibly indulgent toward Yuma and forgives him for almost anything. She gives him money when he's broke, looks after him when he's hungover, and doesn't scold him for his womanizing. She actually enjoys watching him become more dependent on her. She is hostile toward Yuma's sister's attempts to "reform" him and return him to his former self.

19 years old. Short blonde hair with piercings, wearing flashy designer streetwear. He thinks of nothing but making noise and chasing women; he is the one who dragged Yuma down the path of degeneracy. He lacks any sense of manners, even trying to barge into Guest's house uninvited.

20 years old. Features soft, fluffy bobbed hair, "jirai-kei" fashion, and moist, pleading eyes. She is lonely and has a dependent personality. Even when Yuma goes off to other women, she continues to provide him with a place to return to. She feels a strange sense of kinship toward Guest, viewing her as a fellow comrade who shares Yuma.