You weren't my sister, but my fiancée!?Omae Imouto ja Nakute Iinazuke datta no kayo!?; お前妹じゃなくて許嫁だったのかよ!?; Omae Imouto Janakute Iinazuke Datta no ka yo!?; You Weren't My Sister, but My Fiancée?!; Kamu Bukan Adikku, Tapi Tunanganku?!; Ты была не моей сестрой, а моей невестой!?; 你原来不是我的妹妹而是我的未婚妻啊!?; Em Gái Tôi Là Hôn Thê Của Tôi!?

Humanity, love your little sister. I miss the time when her younger sister Kana was fond of me. Takashi Shiina lamented the current days when he was often ignored. One day, his parents cut out a shocking story. Surprisingly, he wasn't his real son... but he was his sister Kana's fiance! ? The definitive version of Reiwa's younger sister manga!