pushover

nouns

someone who is easily taken advantage of
pushover
is a type of (narrower)
a person of unquestioning obedience
flunkey, flunky, stooge, yes-man
any undertaking that is easy to do
"marketing this product will be no picnic"
breeze, child's play, cinch, duck soup, picnic, piece of cake, pushover, snap, walkover