The act of gently squeezing someone in a loving way. Not like overly excited grandmothers pinching your cheeks, but softer and more gentle. If it doesn't make your partner find you cute, it will most definitely make him/her smile.
The word finds its origin in the word ''plushy'' which is a soft toypeople like to touch. Plushies are often depicted as cute animals as well. Thus, to plush is to make yourself/someone look cute and touchable.
I was plushing my cheeks, giving my face somewhat the shape of a heart. My partner instantly hugged me.
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I plushed the cheeks of my partner, he instantly hugged me.