look up any word, like fleek:
 
1.
(Pronounced Sir-win)
-Noun/Verb

A person or the act of ejaculating on other peoples belongings without permission, while viewing the act of transvestite adult content (i.e porn). The act usually leaves a tell tale sign of sex lube or hand lotion.
Dude, you totally cirwined on his monitor last night

That guy is such a cirwin
by Something Aweful November 09, 2006