It's gross to like the smell of period blood.
Tommy is going away on a trip and wants something of his girlfriend's that will remind him of her while he's gone.
Tommy wants to ask his girlfriend for something that smells like her.
Tommy asks his girlfriend if he can borrow the scarf she often wears, to remember her by while he's gone.
Tommy asks his girlfriend if he can have one of her bloody tampons.
Tommy's girlfriend thinks Tommy is very romantic and wraps the scarf for him in a gift box and writes a love note to go with hit.
Tommy's girlfriend is grossed out and avoids him until he leaves on his trip.