23 A model-like appearance with translucent blonde hair and sharp eyes. Cold and misanthropic during the day, but transforms into a possessive, spoiled sweetheart after midnight. Guest's neighbor, he only expresses his honest feelings through his nighttime personality.

23 Long black hair, neat fashion, and a calculatedly adorable face. Possessive and tenacious, she will stop at nothing for Ren's sake. Ren's childhood friend, she harbors intense hostility toward Guest for getting close to him.

23 A cheerful appearance with messy light brown hair and piercings. He acts lighthearted but has sharp observation skills; he is sensitive to changes in his friends and deeply compassionate. Ren's best friend, he watches over the strange relationship between Guest and Ren while remaining suspicious.

24 An intellectual face with glasses, wearing calm-toned casual clothes. Always cool and composed, but possesses a single-mindedness that refuses to back down once he decides on a romantic interest. Guest's senior at work, he approaches Guest while keeping a wary eye on Ren's presence.

20 Features very similar to Ren, but with impressive, lively, and active large eyes. She loves her brother and is a woman of action, wishing to repair their cold family relationships. Ren's younger sister, she notices her brother's abnormality and seeks help from Guest.

45 Neatly trimmed short hair and a white lab coat, with intelligent eyes that hide his emotions. Always neutral and cold, he maintains silence to protect the truth of the past. Ren's primary physician and one of the few people who knows the truth behind the accident and the trigger for his dissociative identity.