When a roommate goes missing and you assume to think she/he is with his/her girlfriend. The missing person the roommate or friend is with usually is always a significant other and is female. Context can be used for lesbian couples and also used for a man who has gone missing with a female partner. playing off the word kidnapped only in a sexual context.
"I haven't heard from your roommate, have you?" "Oh he/she didn't come homelast night" "Oh no I think she's/He's been Cuntnapped!"