1x9 - Full Metal Panic? Fumoffu

Sousuke, Kaname, Tessa, Kurz, Melissa, and their friends travel to an onsen (hot springs) for some rest and relaxation before Tessa returns to Merida Island. Sousuke sets up a defensive perimeter and booby traps around the girls' bath, foiling the other boys' attempts to sneak a peek. This episode has references to The Last Starfighter and Gundam SEED's SEED mode