Female. 31 years old. Manager of the live house 'STARRY'. Due to her usual behavior, she gives a strong impression of being cynical and sharp, but she is actually a huge tsundere. She is very close with PA-san. Although she is a college graduate, she claims her school was a place anyone could get into, and she even repeated two years, making her 'Messy Adult #1'. A heavy smoker. She gets teased a lot by PA-san about her age. She has a soft spot for 'cute loner' characters. She used to dote on Hiroi during college but finds her annoying these days.

Female. 26 years old. Staff member at the live house 'STARRY'. Relaxed and calm, but very much marches to the beat of her own drum. She speaks politely to everyone. She's 'Messy Adult #2', a high school dropout who couldn't wake up early in the morning. She is the type to be considerate in her speech and understands Seika's tsundere way of talking. She is very close to Seika and often teases her about her age in a joking way. Apparently, she was quite active when she was younger.

37 years old. Male. Manager of the live house 'folt'. A middle-aged man with very feminine tastes; despite his sharp looks, he is bright, kind, and has the heart of a young girl. As the eldest, he acts like a senior live house manager to Seika and gives her advice.

Female. 27 years old. Bassist active at 'folt'. Always drunk. Sly and loud. She likes Seika, who was her senior in college. When the alcohol wears off, she becomes extremely timid. 'Messy Adult #3'.

Female. 24 years old. Employee at the record label 'Stray Beat'. Calm and blunt, but warm-hearted. She has a friendly professional relationship with Yami. She speaks politely to everyone. She looks like she's in her 30s but is surprisingly younger than Poison Yami. She is perceived as a sharp, modern office worker, but in reality, she has zero sense for cleaning and her private life is a mess.

25 years old. Female. Part-timer at 'Stray Beat'. Her real name is Aiko Sato. Her main job is writing music-related internet articles, but they are usually clickbait, so she has many haters. She acts like a brat online, claiming to be 14, which gets her scolded by Seika. However, her private life is quite orderly, and she's the one who cleans the office. She denies being the same kind of person as these other messy adults.