She is Convinced that her Half-Brother is a Girl
![She is Convinced that her Half-Brother is a Girl manga](/media/manga/hes-my-sister/volume_covers/0/73313.jpg)
片親の違う弟を妹だと思い込む姉 kataoya no chigau otouto o imoutou da to omoi komu ane
Narumi-kun's sister is convinced that he is a girl. No matter how many time he tells her.
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