Just before he’s about to come, he wants to tell her he loves her, she’s everything, but he can’t, so he curls his head into her neck and gasps and touches her with his teeth and everything stops for a second.
Afterward he rolls onto his side. He can hear her breathing heavily, and then she moves and puts her hand on his shoulder. He wants to push her away, but doesn’t. He wants to get up, or leave, or yell. The hollowness is awful.
He tries to focus on loving her again, and waits for the feeling to pass.