Your black sweater has a nice wintery vibe, you tell your roommate, as it become tight around your body.
The sweater squeezes your waist inwards as your whole body shrinks and your face and shoulders narrow.
Your jeans start to become tight around your legs as your hips widen.
A new gap forms between your legs as new breasts emerge from underneath the sweater.
You smile at yourself and take a selfie wearing the lovely gift, unaware of the changes.