Kahogo de Ecchi na Boku no Ane

The hero is the youngest son, who was born and raised in the family of four older sisters. The sisters got pretty cute over the years. As they grow, their overprotection escalated. The eldest daughter is a nursing teacher, the second daughter is a physical education teacher, and 3 girls and 4 girls are seniors. Everyone goes to the same school as the main character and lives with their brother at home and at school. As such, the eldest daughter is shocked by the result of the health check of the hero carried out at the school, falling below the average growth rate of the same generation, and a family meeting is held. And from that day on, my daughter will be breastfeeding!

Cơ bản là main sống cùng 4 bà chị. Một ngày đẹp trời bà chị cả xem kết quả kiểm tra sức khỏe thì thấy thằng em bị còi cọc chậm lớn nên quyết định họp gia đình để tìm hiểu lí do. Vì lí do éo nào đó nên 4 bà chị quyết định cho thằng em uống sữa để cho chóng lớn.