Buttsession 

To have an obsession with butts.

She totally has a buttsession

Buttsession by PineappleJuice May 2, 2015

Bullsession 

A long informal discussion usually amongst humans of the male variety. The word is most famously used in the Spongebob Squarepants episode"The Original Fry Cook." The word is used by Jim in his flashback. The topic of the discussion can be about anything. It is most common at mature teenage parties.

Guy 1: Dude me and my bros had a Bullsession the other night at Matt's party.
Guy 2: Dude thats awesome I wish I could have been there!

Bullsession by Holyswagness September 25, 2013

Buttssionary 

(adj.) The "missionary position" in which the penis is inserted into the woman or man's anus.

Our sex life is getting boring, lets try buttssionary

Buttssionary by davakon November 15, 2011

ButtCussion 

ButtCussion: Severe fall landing directly on one's posterior axis, causing severe pain to the point of nausea - as in a "concussion of the butt." Falling and landing directly on the gluteus maximus or worse, a direct blow to the coccyx, with pain so severe that it causes concussion-like symptoms.

He jumped up into the air over the frozen swimming pool, cannonball-style with ass pointed down and knees up, thinking the ice would break and he would polar bear it but the ice did not break - Total Buttcussion!!

ButtCussion by AWarrenP November 8, 2012

buttsertion 

The insertion of something into the butthole. Predominantly in a curious and playful way.

She wanted playful anal so I gave her a lego rocket buttsertion.

buttsertion by Paul Perreault December 29, 2017