To Cut, Or Not To Cut? That Is The Question.

This is the shirt! They only had men's sizes, and on top of that the smallest size is men's medium. Needless to say its a tad to big. So my dilemma is, do I cut it and make it into a muscle shirt to work out in? Or should I leave it alone and use it as a pajama top? Mmm. Decisions. It definitely won't work as a exercise top as it'll hinder my range of motion and get too hot. Please, help me make my mind up for me!