デビィ・ザ・コルシファは負けず嫌い

A battle-hungry demon lives deep in the underworld with no opponent strong enough to satisfy her. Out of boredom, she goes to Earth planning to wipe out humanity. She meets Rokurou just as he wishes for someone to play games with. He challenges her to a card game instead of a fight to survive the encounter. She keeps losing, but her pride drives her to keep trying until she can beat him.