Yuma Oda, an ordinary male student, receives a smartphone app called "Hypnos."
The app is imbued with the power of a succubus, allowing the user to issue hypnotic commands to women at will.
Lured by a free trial offer, he tests it on a female classmate—and it actually works!
Returning home in a state of disbelief, he is confronted by a succubus named Rina Arume, who reveals that he has been selected as a candidate to test the app.
Deciding to experiment, he inputs a hypnotic command targeting Fujimiya, a sassy "gal" classmate.
She instantly falls under a spell that turns her mouth into a "sexual disposal unit"; her mouth transforms into a vacuum-like orifice that swallows not only his semen but even his urine afterward.
The next day, realizing that the app has left Fujimiya with only hazy memories of the previous day's events, he unleashes a new hypnotic command to turn her into a "sexual disposal fleshlight" exclusively for Yuma Oda!!
Includes Chapter 1 of the original work, "Succubus App: School Hypnosis."
