NTR Assistant

One day, a suspicious drug that became popular among students from the black market...
It's called "Futanari medicine."
This story takes place in Kivotus in this medicine and among the girls.
 
In vol.1 Satsuki x Gehenna mob (Futanari), Asna x Bani mob (Futanari), and Hanako x Koharu (Futanari) appear.
Each one is included in two videos.
Only one side is Futanari.

Your cousin decides to spend her vacation at your place. She is smart, fun, and very hot.

Summer vacation is finally here! Our story follows Natsu, a timid, effeminate young man who embarks on a family trip to the countryside to visit his aunt Misaki. But just as everyone's getting settled in, a mix-up at his father's workplace forces Natsu's parents to hop right back in the car and drive home, leaving him to spend the remainder of his summer break out in the sticks. Misaki is more than happy to take him in, of course, and so begins a peaceful, relaxing few weeks where absolutely nothing out of the ordinary threatens to disturb his tranquil everyday routine... Bwahahaha, as if!

It isn't long before a self-proclaimed magical girl named Chitose worms her way into Natsu's life, but her boisterous intrusion is the least of his problems. An eccentric candy seller, an insecure wanna-be teacher, a pink-haired loudmouth... Not to mention, his aunt's strange behavior around the topic of the outdoors. Surrounded by misfits, it soon becomes apparent that Natsu's real summer homework is to learn more about the women around him and help them with their problems. And yet, with only 30 days until his parents pick him up, is this one assignment he's fated to flunk, or will he pass with flying colors?

The main character is a self-proclaimed female ninja.
Despite her cute appearance, she has mastered both martial arts and ninjutsu.
One day, she is caught in a trap set by a mysterious organization and given a drug.
The effect of the drug is that she continuously emits pheromones that turn her uncle into a sex monster.