My Petite Girlfriend Is My Dad's Sex Slave

Mayu has the perfect relationship with her boyfriend Riku. The pair are so short that their classmates even dubbed them "the miniature couple." But Riku's father is nothing like his mild-mannered son. Strong, intimidating, and physically huge, he has his eye on Mayu... and she won't be able to deny his demands.

(Source: Fakku!)