I Keep Starting Over, but I Can't Escape the Demon Lady's Grasp

He made a contract with a demon and gained the ability to be reborn endlessly.

The price is turning into a girl, but that's no problem!

"Look, that's an evil demon. It has three times as much protein as beef. All we have to do is sneak up behind her, and then..."

Crunch~

The protagonist, dead.

(P.S. Don't ask why the blurb mentions exercise.)