Benisato's ability is the control of snakes, that actually come from her body in many shapes and forms. She also has the ability to shed her skin like one. We first see her in action when Jubei is trying to recover from his battle with Tessai. She appears naked in front of him, revealing a body covered in serpentine tatoos, tatoos that come to life and try to kill Jubei. He easily defeats the snakes and gets a hold of her, only to see that she is merely a cast-off skin left as a decoy.
She is Gemma's lover and the devil that discovered who Jubei was after Tesai left an imprint of Jubei's face in his hand. Also in her power is the ability to create cast-off skin "puppets" that she controls. We see this in the old woman praying at the temple. She is very taunting about her relationship with Gemma to Yurimaru, which is reason for the "tension" between them.