In addition to her general appearance as Black★Rock Shooter, her eyes have a concentric circle pattern, a trait she shares with other characters in the OVA. She shown to be around 156-161cm tall, while her human counterpart, Mato, is 155cm.
She is depicted as a calm and collected girl, not speaking at all until her confrontation with Mato, near the end of the OVA. She also does not focus on anything except the most important thing she has to do at the moment.
She is shown to be very skilled in fighting, despite being quickly taken down by Black★Gold Saw in her first shown battle. Black★Rock Shooter is able to fight evenly with Dead Master, despite appearing to try not to hurt her.
Black★Rock Shooter is initially shown in her world, fighting against Black★Gold Saw for an unknown reason. Though the silhouette is unclear, she is impaled by Black★Gold Saw and left to be crushed under falling rocks.
Sometime after this event, Black★Rock Shooter meets Mato, her human counterpart, who is distressed over the disappearance of her friend Yomi Takanashi, who had merged with and vanished with her "other self", Dead Master. She speaks telepathically with her, asking if she wants to save her. Mato answers that more than saving Yomi, she wants her back with her. Hearing that answer, Black★Rock Shooter merges with Mato.
Black★Rock Shooter appears at a broken ledge. She is now wearing a long trench coat and sporting a new weapon, the ★rock Cannon, along with now displaying her well-known scars. She crosses many different scenes and finally ends up at a castle which turns out to be the residence of Dead Master. Initially, her reasons for fighting or pursuing the Dead Master are unknown.
Inside the palace, Black★Rock Shooter finds her opponent; she holds out her hand, and the Dead Master responds by attacking. The two begin their fight, with Black★Rock Shooter igniting her eye and powers, both of them seemingly equal.
Dead Master manages to ensnare Black★Rock Shooter in a web of chains, where she is apparently trapped. However, Black★Rock Shooter gains the strength to break free of her chains with her bare hands. Once again, she holds out her hand to Dead Master. Dead Master is confused, and when she falls off a ledge, Black★Rock Shooter pulls her up and embraces her. Dead Master, unable to handle this, escapes from Yomi's body and dissolves.
- She displays an ability to destroy the Dead Master's chains with her fists. She does this just after breaking out of the Dead Master's chains.
- Like her anime counterpart, she displays high agility, stamina, and strength, and seams to be able to survive attacks that would otherwise be fatal.
- She seemed to know where the Dead Master was without finding out from external sources.
- She does not have her jacket prior to being stabbed by Black Gold Saw.
- She seems to be somewhat kinder than the Dead Master, as she asked if Mato was willing to merge with her.