"MSF, huge ugly teeth, glasses and no life. Looking for one night stands or a f*ck buddy even though I'm the ugliest man on the internets."

Guy: I saw a guy with huge forceps.
Girl: Forceps?
Guy: please MSFS and tell me youre kidding

boy: so what chu wanna do when we chill?
(girl)anything really, but quite honestly im MSF.
boy: wha dat mean?
(girl) i mentally sexually frustrated
boy:i thought you was a virgin..
(girl) i am. in my mind i want sex badly, but physically i not feelin it as bad..
boy:lets do it! i can help ease your mind ;)

friend1:im sexually frustrated
friend2: im MSF
friend1: huh?
friend2: mentally sexually frustrated. im horny mentally
friend1: oh, im horny physically
*what have our lives come to*

When a man is talking to a group of women (can be generalized to other social interactions), sometimes one woman, usually the least attractive of the group, is not getting enough attention. While everyone else is laughing and having fun, she tries to interrupt by saying, "let's go somewhere else," or "I'm tired;" or verbally attacks the male suitor. She is an MSF.

Stranger 1: hey MSF
Stranger 2: No way, FSM!

Jenny is Kirsten's newest MSF.

Steve: Man that pisses me off!!!
Dan: What is wrong with you? it it MSF time?