You can’t tell anyone about this first love! A forbidden “brother and sister” love story that will make you faint in agony. A meltingly sweet love comedy by Kei Hozumi, a master of lovey-dovey pure love! “Onii-chan, no one can know about our relationship, okay?” A high school boy, Yuma Chiharu, is in love with his younger sister, Chimari. The relationship between the two siblings is a highly confidential affair. If the school or their parents find out, the worst that can happen is that they’ll be separated! They must not let that happen! But then― “Hey, who was that girl you were kissing the other day?” To his surprise, his senior at school, Kii, witnessed his first kiss with Chimari… When they’re caught making out, the secret of the siblings is in jeopardy! He’s not going to let anyone get in the way of his sister and him―! What would happen if I actually tried to have a serious love affair with my too-cute sister? A straightforward love comedy about an older brother and a younger sister who are in love with each other. A story of pure love between an older brother and a younger sister that will make you faint in agony without being found out, starts now!