Glomitz
A person who's only goal in life is to leach off of the success of others, who takes advantage of others at every opportunity and has neither the drive nor ambition to do anything worthwhile. A person who defys all commonsense whenever it suits.
My unemployed brother forces his wife to work while he sits at home playing World of Warcraft all day. When she gets home, she must serve him his dinner at the computer. He is such a glomitz.