|Name in Japanese||ユウ|
|Appears in||OVA, Anime Series|
|Voice Actor (Japanese)||Kana Asumi|
Black★Rock Shooter (OVA)Edit
Yuu is excitable and perky; however, she is shown to have a dark side. She is also very possessive of Mato, and has an awkward time whenever she is hanging out with Yomi.
Yuu first appears when Mato gets injured during basketball practice, and she tends to Mato.
She is a first year student who becomes accelerated to second year. She ends up as the main cause of Yomi's fall into possession by Dead Master, as her possessiveness of Mato and the fact it is difficult for the three to be as close as two of them would be which creates jealousy inside Yomi.
When Yomi vanishes, Yuu encourages Mato to cheer up, although she seems more concerned about Mato than Yomi.
After Yomi and Mato reconcile, they invite Yuu to come along with them. However, Yuu feels "left out" somehow and approaches them with a dark expression. It is implied she is the next problem Mato or Black★Rock Shooter will have to face.
Her "other self" is not explicitly shown but is implied to be Strength as the two have the same hairstyle, and Strength is shown to be ominously approaching the fighting Black★Rock Shooter and Dead Master while Yuu's dark feelings are starting to surface.
- Yuu's last name was never shown in the OVA. The 2012 anime gives the anime Yuu incarnation a surname of "Koutari"; however, this may or may not apply to the OVA.