Yumi Shiina is a 26-year old bartender working at an underground bar in Shibuya. A cognitive manifestation of Yumi as a phantom idol was created by Merope from Nagisa Kamishiro’s cognition, also known under the codename Phoebe. She used to be an active dancer in her school's dancing club, experienced in different kinds of dances like belly dance, but later she quit. Now, she uses her dancing skills on her bartending as an attraction. In her social link, she's seen to be advanced in making all kinds of drink with an unmatched amount of flair, making non-alcoholic mocktails for the protagonist to try.

Voice Description: Medium-female vocal range. Composed and work-orientated, she's also extremely charismatic and can change her tone on a whim depending on the situation.