The Filthy Bucket (汚れたバケツ Kegareta Baketsu ) or simply a Bucket (バケツ Baketsu ) is an item found in Corpse Party and Corpse Party: Book of Shadows. It is a rusted old bucket filled with clumps of old meat and maggots.
It is found next to the entrance of the Girl's Lavatory, but can only be obtained after Naomi discovers Seiko hanging inside the lavatory. While Naomi fails to use it for its intended purpose of giving it to Seiko as a footstool, it is not necessary to achieve the chapter's ending.
It is mentioned again while the player controls Satoshi, where it is found inside the bathroom stall where Naomi hangs herself. The player must avoid choosing to stand on the bucket to save Naomi, or else it will break and cause Satoshi to drop the still-hanging Naomi, killing her. This would lead to either a Wrong End or an Extra End.
Corpse Party: Book of Shadows
Episode #5; 『Shangri-La』
After accepting the ghosts request to help him get his head back, Mitsuki and Masato decide to carry it using something other than their hands. They find the bucket near the staff room and use it to carry the head. Unfortunately for the two, the ghost gets violent and breaks the floor beneath the two.
You can only pick up the bucket in the wrong end route.