The act of having sexual intercourse with your best friend and a female(s). Another variation of group sex or 3 somes. Getting weird can happen at any time, place, or situation. Usually fueled by excessive drinking and getting chased by your best friend naked.
~Ben and Brian got weird with those models last night.
~Is anyone down to get weird tonight?
~"Man that girl is trying to get weird, lets grab them cheeks"
~If she isn't getting weird than I'm drinking her beer and going home