Tell her what's going on
From Create Your Own Story
You tell her that the teacher is looking at a porn magazine. She looks through the window with you. The teacher unbuttons her suit and lets her breasts spill out. You feel your cock rise in your pants. The teacher removes her skirt and starts to rub her pussy. You contemplate masturbating but you know there is a girl beside you. The urge becomes unbearable so you unzip your pants and stroke your hard cock. You are pleased that the girl hasn't seemed to care, notice, or even glance over.