Panty & Stocking with Garterbel S1/E13

Having lost her powers, Panty is kicked out by Garterbelt and moves onto a farm with an old woman who, unbeknownst to her, is in league with Garterbelt and persuades her to stop Corset from using Brief to unlock Hell's Gate. Panty has sex with Brief, losing her virginity and restoring her powers. Stocking returns to help Panty fight Corset and the Demon sisters. Brief accidentally unlocks Hell's Gate with his penis, unleashing a massive Ghost that begins destroying Daten City.