Sex Chudoku -That Girl To Slavehood-

This video is gamepop game "Sex Chudoku -That Girl To Slavehood-" from the Studio Courreges Ace. The game was released in December 2011. 

The protagonist of the story is a fat and clumsy third-year student. He's an otaku and a pervert. Once going to the University, our hero hurt his leg and the only one who helped him, was incredibly beautiful girl Ayano. She was pure and innocent, so our Otaku-kun fell in love at first sight. Once our hero saw Ayano-Chan walking with some guy under his arm. It was Teruo-kun - the most beautiful and popular guy in the University. 

"Why? Why did she let him into her house? She should be mine! I won't forgive her for that!"his heart was broken, and a plan of revenge was brewing in his head...