Full Metal Panic! - Season 2 Episode 8 A Goddess Comes to Japan (Part 2: The Hot Spring)
Overview: 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.