the act of having buttseks where the male genitalia penis is inserted into either a man or woman's anus, without warning, and screaming "SURPRISE BUTTSEKS" upon entering the rectum
amy:so, jill as i was saying, i truly thing that the northern hemisphere should be considered new zealand and the southern should be testicleville
jill: but on the contrary, i do not bel--
mike:(while entering the rectum) SURPRISE BUTTSEKS!!!!!!!!!!!!!!!!!!!!!!
When the spy, featured on the PS3, and PC game, Team Fortress 2, attempts to stab you (one of the 8 other male characters) in the back, but instead, gives you "Surprise Buttsecks" after, the trending songs and videos on YouTube.
*The Blue Scout, is defeating the red team when suddenly-*
Spy: "SURPRISE BUTTSECKS", BUTTSECKS, B-B-B-B-B-BUTT-SECKS!!
A: Me and my gf had a really romantic datelast night. Saw titanic.
B: nice
A: yeah, and then when that stupid boat sank, i gave her surprise buttsecks!!!1 kekekekeekk
B: WTF??