get (one's) claws into (someone)

To exert one's influence over another person. Bobby's new girlfriend must have gotten her claws into him—have you seen the way he's dressing these days? Once that advisor got his claws into the president, there was a noticeable shift in her priorities. Was this really your decision, though? We all know Anita's gotten her claws into you.

get your claws into

enter into a possessive relationship with someone (used especially of a woman who dominates or manipulates a man). informal