A word used to describe the relationship between two males, whom have found they had intercourse with the same male, mutually known by both (much like eskimo brothers).
Chad: Dood you will never guess who I banged last night.

Brad: Who?

Chad: I totally fucked the shit out of Chet!

Brad: Ohhh man no way! I totally fucked Chet in the ass too!

Chad: No way! When?

Brad: Remember when Chuck had that awesome Christmas party last year? Totally pounded Chet in Chucks champagne room then, he was so loose!

Chad: No way! That makes us unicorn brothers!

Brad: Fuck Yeah Unicorn brothers for life!

*Brad and Chad then preform a high five

Chad: Dood, Chet is such a butt slut...
by WIldBillBigCock December 17, 2015
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