Appli de Hentai: Pool no Sukumizu Ningyo

A young man discovers a mysterious app on his phone that claims to grant any wish. Intrigued, he decides to test it at a local swimming pool, where he encounters a beautiful girl swimming alone. The app activates, transforming her into a mermaid-like being with a school swimsuit, blurring the line between fantasy and reality. As he explores the app's power, he becomes entangled in a series of surreal and erotic encounters that challenge his perception of desire and consequence.