A nocturnal mom who by day is dress as a fat old mom and by night takes off her fat suit and is a hot model, is usually very horny and has sex and or performs oral sex on her children's friends when they sleepover. Not to be confused as Robin Williams.
Justin: Steve is such a fag the only reason I hang out with him is so i can sleep over his house and bang his mom who by the way is a Mrs. Doubtfire.
Mick: Yeah she is a Mrs. Doubtfire; she cooks me the best cookies during the day and at night she gives me the best dome I have ever had.
Justin: Lets go to Steves to night and double team his Mrs. Doubtfire.
Mick; sounds like a plan