You improvise

The pair of topless teens stare at you with glistening eyes. You don't feel your 48 years right now. Grabbing the pair of red-heads and throwing their lithe young bodies onto your bed had come with a rush of power that had caused your cock to swell. Pinning Sally's slender frame against the door with yours had only added to the feeling of dominance, but best of all had been watching the sisters meekly pull off their shirts at your command.

As a biology teacher you were well aware of the behaviour of primates where only a single dominant male would mate with all the females in his troop. A successful alpha male would inseminate as many fertile young females as possible to pass on his DNA - you stop that line of thought before it gets out of hand. Your cock is twitching with need, but you fight your primal urges, looking at the sisters with calculating hunger.

"Get off the bed, and turn around," you rasp hoarsely. Wide eyed the girls obey, Sally looking over her shoulder at you with doe eyed anxiety, her slender arms covering her tiny breasts. You look around the room, seeing a hand mirror laying on the dresser. "Bend over and put your hands on the bed," you order, your voice clogged with hunger.

"Sir? Please sir, what are you going to do?" Grace asks in a shy quiet voice.

"I'm going to deal with you as vandalising teens should be dealt with," you answer, picking up the mirror. "Now bend over. I won't tell you again."