Wrapped around someone's finger Informal

To be completely under someone’s influence or control, doing whatever they want, usually out of affection rather than fear.

It’s most often said of a doting parent and child, or of someone charmed or infatuated into total compliance, rather than of coercive or hostile control.

The phrase draws on the image of a thread or piece of string literally wound around a finger — something small, pliable, and completely under the winder’s control, twisted this way and that at will. The metaphor of a person being manipulated as easily as a string around a finger is documented in English from the 1800s, and the specific passive construction “wrapped around someone’s finger” became the standard modern form, most often applied affectionately (a grandchild who effortlessly gets whatever they want) rather than as a description of malicious manipulation.

Her little brother has her wrapped around his finger.

The client has that lawyer wrapped around her finger.

He’s completely wrapped around his girlfriend’s finger.

A: Why did you buy him another toy? B: I don’t know, I’m wrapped around his finger.