It fixes any broken parts of the Witch using parts from its own body. Though it's not doing it for the sake of the Witch, it simply loves fixing things. It will happily repair anything, even if it's not a Witch.
Concentrated lumps of hospitality that use their own bodies to repair the witch’s broken parts.
They’re not really doing it for the witch’s sake in particular, though. They seem to simply enjoy the act of repairing, and they show hardly any discretion when it comes to broken objects besides the witch.