While witches are commonly solitary beings, it is not uncommon for them to join forces in order to take down and share an otherwise difficult prey, in this case, another witch, of the black-white variety.
As opposed to the methodical precision of the hunt, the feast itself is no less messy than any other predatory carnage.
If you pay attention you can hear, between slurping and licking sounds, the downed witch's gasping in agony. Wait, that wasn't agony.