When someone sends you a fucked up pornographic image over a text message.

Combination of brain, anal, sex, and text.

It is essentially a mind-fuck over a text message.
Steve: Yo, chris did you get that brainal sext i sent your daughter???
Chris Hansen: Yes, I've been meaning to talk to you about that... why don't you take a seat...
by armadilloracer March 9, 2010
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