Otokonoko Academy! ~My Fateful Encounter with Three Otokonoko, and the Love That Followed~

The protagonist began dating a femboy.
When he found out that the femboy had never even masturbated, he decided to teach him about sex through videos and other means.
However, when he saw the femboy getting embarrassed watching a pornographic video, he found himself becoming aroused.

Thinking about doing something to the femboy, the protagonist skillfully convinced him to wear women's underwear and laid him on the bed.
It's only natural for a lover... he said, and began to caress his body.
At first the femboy was flustered, but it seems he had masochistic tendencies, and the more he was teased, the more seductively he began to moan.

And finally...

The protagonist, Kazama Yukiya, was living a student life while earning money through his own method of exorcism and purification, in addition to receiving financial support from his parents. One day, men in black suits appeared at his place and forcibly took him back to the countryside. They were the messengers of the "main family", and Yukiya is informed by the head of the Kazama family at the mansion where he was taken that Hisame, a shrine priest he had adored like a real brother since he was young, has passed away.
Astonished, Yukiya is immediately told by the family head, "Become the shrine chief to protect the company and take on 'a certain troublesome matter' with the shrine maidens. You have the talent for it." Confused, Yukiya hears about the "troublesome matter" from the three charming shrine maidens and reluctantly accepts the task.

Academy Love Saga: Tennis Angels EX is a Tennis game with dynamic action-oriented gameplay. Control cute girls and compete in exciting matches with strategic positioning and masterful usage of special skills. Enjoy the hilarious story of how a retired Tennis coach regains his former glory.
Execute charged shots to place the ball perfectly in your opponent's court, or rush the net for intense close-range play, all while risking a skilled lob from your adversary. Be cautious of your stamina, as running out can lead to serious trouble. Build up enough Tension to unleash special skills and overpower your opponent. This game tests both your physical prowess and strategic thinking.
Enhance your characters by leveling them up to boost their stats and unlock powerful new skills for matches. Buy equipment that complements their playstyle. With a variety of characters each featuring different stat growths and skills, you will need to unlock them in Campaign Mode. Experiment with different players to find the one that fits your playstyle the best.
For those who appreciate the narrative, this game offers plenty of engaging "plots" (in every sense). Enjoy a humorous and dramatic storyline as you take on the role of an overlooked coach winning the approval (and affection) of his beautiful female club members. Each character has their own "Love Stories" that unlock gradually as you train and level them up. Gotta catch... cough train them all!
Bring your trained characters to the epic Global Underground Tournament and showcase the results of their hard work. Face off against formidable opponents in the tennis world. Will you emerge victorious and claim the title of Supreme Champion?
Enjoy hot and erotic "special" scenes with the girls you have conquered. Not only girls in your club, you can even tap the girls in the Global Underground Tournament after they were defeated. The winner takes all!