scrounger

1. He is just a scrounger, who lives on other people.
   他正是一个小偷，专靠损害别人过日子。
2. You're a parasite, a scrounger, living off other people's efforts.
   你是个寄生虫，到处伸手，靠别人的劳动生存。

noun

1. someone who mooches or cadges (tries to get something free)

   Synonym:    moochermoochcadger