When warring robots from outer space land in Daten City, Panty & Stocking eat their cores and become robots themselves to carry out their sibling feud.

After collecting the necessary Heaven Coins, Stocking manages to return to Heaven. However, due to her erratic sex life, Panty is forced to stay behind and redo her quota, with Garterbelt forbidding her from having sex. She and Brief go to a party, where a devious plan is being concocted by Corset and the Sisters, and Panty finds herself losing her angelic powers.