The genie gives you a pencil. You wonder how it can help you put a prank on your friend. You see a photocopy of his ID card on the table and can't resist... You start drawing long hair on the picture. Then, you draw some lipstick and finally, you replace the M of "Male" with a F of "Female".
To your surprise, a sexy girl enters the room... She looks like... a female version of your roommate. She says panicked :
"- What the fuck just happened ?! I was watching TV, my hairs started to grow longer, then some lipstick appeared on my face and finally, my whole body became female !"
It IS your roommate ! You just got a magic pencil !