Age: 19
Height: 149 cm
Weight: A lot of apples
Birthday: September 12th
Blood type: AB
Three sizes: Huge-Average-Probably Average
Hobbies: Composing poems in the middle of the night, Attending idol events and concerts

Neurotic and contradictory, Riamu is a follower of the Menhera subculture and an idol otaku. Riamu makes the decision to become an idol due to her desire to quit school and as an attempt to turn her life around since Riamu fears aging out of her teenage years and feels she has hit a dead end in life. Riamu uses the catchphrase yamu ("I'm so sick"), and frequently makes references to the fact that she is lonely and depressed, as well as desperate for any kind of attention. Riamu seems to have incredibly low self-esteem and does not see herself as having any good points.

Riamu utilizes a lot of current otaku internet slang, primarily from Twitter. Riamu is terrified of being hated and begs her fans to be nothing but kind to her, but at the same time states that she doesn't care if she causes controversy as long as she gets attention and sells. Riamu's Valentine's Day 2019 lines imply that she thinks people coming to hate her is something inevitable, so she wants to receive as much love and attention as she can from them before it happens.

Riamu seems generally distrustful of idol otaku, despite being one herself, stating that she doesn't trust otaku who change the idol they support, and that she only has faith in otaku who attend events and concerts in person. She seems suspicious of idol otaku who claim to support every idol in a group (known as daredemo daisuki or DD), because she does not believe they will actually pay attention to Riamu herself. It can be inferred that these attitudes likely stem from Riamu's low self-esteem and her desire for her fan's undivided attention and support.

(Source: Project-iM@S)