Tsun M! Gyutto Shibatte Shidoushite The Animation / Tsundere Masochist! Tie me up tightly and train me

The hentai is based on a visual novel of the same name by studio Ammolite, released on August 25, 2017. 

"I heard a strange sound..."

On the bed in my room lay a naked lewd girl with her hands bound behind her back and a gag in her mouth. 

"Why? How did this happen?...

-This is one of my students at the college where I teach. How could this have happened?"

Characters:

Yoshinori Koike (Koike Saki) - A girl with beautiful juicy breasts and a lovely butt. She is the head of the student swimming club. She has been in love with our hero for a very long time.

Takeshi Hamaoka - The main character and chairman (curator) of the student swimming club. He is short and a little plump. What turns him on the most is sadomasochism and various forms of tying up girls.