Shameful Body(2009)

Yamashii Karada

When you're a sadist and the boy you love is a masochist, picking on him is a pleasure.

Pain doesn't affect Yoshie... no, that's not quite right; it feels good! Sensei's forceful massages at the Seitai Clinic are the best. But Sensei's solemn and bone-obsessed son, Mikawa, is secretly listening to Yoshie's breathless moans! Is it only a passion for bones that excites Mikawa? Yoshie soon realizes that pain in your heart isn't the same as pain in your body.

Extra story: A young man loves the pâtissier who works at his dad's café, but with their age gap, will his love ever be taken seriously?

(Source: DMG)