Based on the erotic game by Dwarfsoft. 
 
He is a womanizing private tutor. It's time to bang down his super sexy student and her mother! 
 
The protagonist Nozomu Kurisu is such a thoughtless man of sexual desire. He is a "d*ckist" university student whose life is ruled by his d*ck, as if a word "womanizer" wears clothes and walks on the street. 
 
Having enrolled in a famous private university in order to take a distance from strict and square-headed parents, he makes money as a private tutor taking advantage of being a student at the famous university. With his muscular body and proficient verbal techniques, he has built several physical relationships with his students and their mothers. 
 
Currently, he teaches Tatsunobu Hatsufuji's daughter. His family is really ideal. Despite the fact that his wife Akari is 18 years younger than him and his daughter
Shizuku is not blood-related to him, the family members live in harmony. 
 
Considering what Nozomu has done before, he should have already f*cked the mother and the daughter who strongly arouse his d*ck. However, because he plans to find a job using the father's connection and they provide him a very nice working condition, he founds that making a mess in their family is somewhat too much against the public moral. Just recently he has dumped all of his friends with benefits so he has been sexually frustrated as strongly as ever before... But his sense of morality prevents him from going all the way as he wants. However... 
 
"I want you to get laid with my wife... Akari." 
 
...The one who shakes up his remaining reason, common sense and gratitude is the father of the family, Tatsunobu. Based on the secret contract, a lustful feast begins with a cuckoldry drama approved by the husband...... 
 
(Source: DLsite English, edited)

Yarichin Kateikyoushi Netori Houkoku: Dosukebe Kyonyuu Oyakodon