Based on an adult game by Atelier Kaguya.

Kateikyoushi no Onee-san The Animation: H no Hensachi Agechaimasu

Touya returns home during summer vacation to find 4 older women (Rio, Nagisa, Amane and Sara) awaiting him. They have been hired as live-in home tutors for Touya. However, his lessons are not limited to book-learning...