Usually in online communications, when one person says something very clever/funny at the same time to a person who was asking a stupid question. A third person may acknowledge the replier's effort by saying "Marry me!", effectively praising him/her on the cleverness of the reply.
OP: Do you like Justin Bieber?
Person 1: Yeah, I bet she has a tight vagina.
Person 2: @Person 1; MARRY ME!
Person 1: Yeah, I bet she has a tight vagina.
Person 2: @Person 1; MARRY ME!
by hugooguh February 03, 2013