He is number 8 level 10 breaker who is not officially registered in Society. He is oblivious to Eto Misaki's feelings.
When he was a kid he was the one who found Rose when still she was in a egg on mountains. He stops it from falling of the cliffs when it starts to move and crack open. When it opens he gets surprised seeing her in it and slips and falls of the cliff. At that instant Rose jumps and catches him from falling and protects him. It was told by Eriko that she might have fallen love with him when she saw him first there. He tells about this in episode 2 and also tells that it was a coincidence that he found her, as it was due to him getting separated from his parents while climbing mountains and just happen to see the egg which he got interested.
He is actually scared of Cursed Precious and at starting he sees Lost Precious no different from Cursed Precious and tells he doesn't want to get involved with them.
At first he couldn't remember that it was Rose who saved him from falling off the cliff. Later he opens up to her and even becomes her Engage Partner.
In the last episode of the anime, he comes to terms to his true feelings for Rose due to Maruga convincing him. He decides to get her back from Onyx and goes to stop him from leaving the city. After he meets Rose, he tells her that he wants to be with her because he loves her. Later they kiss to form Love Engage and Onyx disappears.
