Obtained from the Impetuous Impulses Minigame as a reward for trading 3 baby implings, 2 young implings and 1 gourmet impling with the Elnock Inquisitor.
Can also be player made.
Uses:
Carrying a vial of imp repellent in your pack reduces the chances of imp defenders rescuing captured implings from your inventory.
It also can be used to make an impling jar by using it on the Rimmington Chemist's indoor lamp oil still and then using a butterfly jar on it.
Notes:
Imp repellent is made by adding flowers (grown from mithril seeds or from farming nasturtiums, marigolds or rosemary) or flowers/herbs from Oo'glog to a vial of anchovy oil.