A phrase someone says when a man does something polite or charming. It means to get a respectful boyfriend like the guy you are referencing is to his girlfriend.
Jenna: Hey Charlie, can you go get me some more water?
Charlie: Sure (gets up to go get Jenna water)
Jenna: Can you also grab the ketchup?
Charlie: Yeah (grabs ketchup and water and brings them to Jenna)
Alice: Get you a mans like this!