Usually used in reference to a Charisma Man in a relationship with a smarter - and usually Asian - female. The man has been tricked into unwanted marriage via a "surprise" pregnancy or by other underhanded means (the trapper often executes a well-formulated plan which the trappee is blissfully unaware of).
An interjection - sometimes an adjective - always said in a shouty whisper.
A: Did you hear EFM got married to his girlfriend?
B: Really?! I thought he was going to dump her.
A: Yeah, but she got pregnant...