Bolt Cutters

Guest House B1, Guard's Area: on the workbench (the same one as the List of Names).

Cut two chains: the one on the cell door in the Guard's Area (where Mia is) and the one on the chained wardrobe in the Back Corridor (1F, next to the Kitchen door), which holds the Fuse.

They take 2 slots. No further use after the Guest House.