misewell means "might as well" and is used by girls who receive a 1210 or lower on their SATs.
tor: I am driving by your house.
katrin: Well you misewell come in and watch Monkeybone.
The slur of "might as well"
It's just they way it's said, mise well doesn't mean anything.
It's said more like "Mize well"
Thad: PARTY AT PHIL'S HOUSE!
Randy: You goin to the party at Phil's house?
Ron: Well, I mise well, I've got nothing else to do.
Comes from the aussie slang for "May as well". Use when lazy and/or aussie and/or drunk.
Midge: Yo, Anf, wanna go scout some poon
down at local convenience store?