To be a yes man, in the style of Uriah Heep.
Someone like the fictional character Uriah Heep.
A fictional character, Uriah Heep, in the 1850 Charles Dickens novel David Copperfield, noted for his cloying humility, obsequiousness, and insincerity, the stereotypical yes man.
To behave like a toady (to someone).
toadlike
A sycophant who flatters others to gain personal advantage, or an obsequious, servile lackey or minion.