If a Druid equips this weapon and transforms into Cat form, they will appear as a fire cat (the same model that Staghelm transforms into during his boss fight).
Once the druid has activated the fire cat appearance, they can switch to another weapon. The fiery appearance for cat form will be lost once combat ends, though. Collecting the staff as an appearance unlocks the flame cat form appearance in the barbershop so it can be used permanently.
Patch 9.0.1 (2020-10-13): Collecting the staff as an appearance unlocks the flame cat appearance in the barbershop.