Seriously. How tall is she? What's the average height or lowest height of schooldoors in Japan? We could add 5 cm to that, because she hit her forehead.
EDIT: Also of course, suddenly boobs. He doesn't look all that unpleased.
@Qelix : I've got 2 friends that went to Japan this summer, they're 180 and 190 cm, and they kept hitting their head so yeah, they have small doorways.
Average height in japan is 5'5" for women and 5'7" for men and while doors are usually 6'6" - 7'0"+ in America but in japan doors start as low as 6'0" so seeing that she's probably around 6'1" or higher.