Vulcanic Butt Water

Vulcanic Butt Water is an activity where water or some kind of liquid (beer is the most common) ir poored trough ones back, passes trough the butt crack and ends up in the other person face. The first mentions of this activity appeared in Budapest-Hungary at a party hostel called Grandio Party Hostel by a group of Portuguese individuals in a bachelor party called "Bizeus Bachelor Party"