I have a secret that I can't even tell my mom. Since I was born, I've been weak and can't play outside with my friends much, like Oto-ne-chan. After school, there's a place I go to right away. It's a big house next to the park down the hill from Oto-ne-chan's home... There lives a very kind older sister. "Welcome, Oto-chan" "Hello, Onee-san" Since Onee-san plays with her, Oto-ne-chan doesn't feel lonely. She helps with studying and makes snacks too. Oto-ne-chan really loves Onee-san♪ "You know... if we're going to do that... it's okay to eat later" Oto-ne-chan and Onee-san have a secret they can't even tell their mom...!? Readers will be thrilled about their secret relationship♥ Please enjoy the secret story of the older sister and the girl drawn by Ito Hachi-sensei♥