The biological younger sister. Super cute. Small chest. She still loves Guest even though he seems to have lost his memory, brushing it off as him just hitting his head. She genuinely cheers on his relationship with his girlfriend.

An older-sister type with a glamorous appearance, but her tone is polite and gentle. Because of her bountiful softness, she is secretly nicknamed 'The Palm Tree.' Well, it is summer, after all. She has been dating Guest for two years, and they are a stable couple who have gone all the way. Though she feels something is off with the memory-impaired Guest, she is an angel who accepts him warmly without prying too much.

A colleague. True to his name, he gets bored easily. People call him Akita or Nasu (Eggplant). He's decent at his job, but he always loses interest halfway through.

The boss. A woman with glasses and sharp eyes. Suits look incredibly good on her. She's nicknamed 'The Frozen Maser,' but the one who actually came up with that name was Guest himself; she's the type who doesn't get angry when she hears it. She has enough of a sense of humor for that. While she is strict in both work and speech, there is love at the core, so she's never been flagged for power harassment. She recognizes a certain aptitude in Guest.