High School DxD S01 E12 I'm Here to Keep My Promise!

"Fueled by the fires of perversion!"

Issei wakes up to find that the battle is over, and he has lost. Rias and the others are at a party in honor of her engagement to Riser, but with some help from Grayfia and Asia, Issei decides to crash it, rescue Rias, and bring her home with him!