goody-goody

nouns

a person who behaves extremely well in order to please a superior
goody-goody
is a type of (narrower)
a person who tries to please someone in order to gain a personal advantage
ass-kisser, crawler, lackey, sycophant, toady

adjectives

affectedly or smugly good or self-righteous
goody-goody
is similar to
morally admirable
good