My Popular and Perfect Boyfriend's Slovenly Face Is Mine and Mine Alone

Shintarou is tall, well-educated, and has a bright future ahead of him... It's no wonder that he's super popular with the ladies.
However, being his girlfriend, I'm the only one in this world who knows the side he doesn't show the public.

No one could imagine that he moans from having his nipples twisted and scratched by me.
Also, he gets off when I slowly lick his penis and edge him...

However, this is where my dominance over him ends.

"You've gotten real good at teasin', huh?"
"Thanks for puttin' in so much effort, even though yer actually a hardcore masochist."

My boyfriend says that as his expression becomes more sadistic. Thus begins the sex in which our positions are completely reversed.

Official Translations:
English, S.Chinese, T.Chinese, Korean