Based on Adult Game by Atelier Kaguya BerkshireYorkshire.

Advanced series from Kateikyoushi no Oneesan The Animation: H no Hensachi Agechaimasu. The days of Touya with 4 Beautiful Teachers continued again because his father left him again, entrusted Touya with these four Beautiful Teachers. The harem story full of beautiful teachers still continues in the summer.

(Source: Nekopoi and Has Been Translated)