Mush Bag 

used to insult someone who is an idiot and brains gone to much because of repeated drug use.

Yo, that jeff piercey is a fuckin mush bag

Mush Bag by Steve Thornhill January 22, 2008

Mushbag 

/Mush-bag/
adjective

Mushbag is a word to describe someone who is too soft, too weak, or cannot take a punch.

my brother is such a Mushbag I'm gonna Kazooki him at 4:20 pm.

Mushbag by TheBlackMist May 9, 2017