He's completely enraptured, soft noises escaping him as she works her mouth further, but he's gone otherwise totally still, barely breathing.

"T-Towa..."

His voice is soft, reverential. He's watching her without blinking, completely caught by how she looks and the concentration she's giving this, let alone how good she feels. He can't really look elsewhere even if he wanted to, which he definitely doesn't.

She can't really respond he knows, but he's sort of choked on being able to get anything else out so they're almost even there.