Kyonyuu JK Saiin Choukyou: Kimonii wa Imouto wo Milk Nomi Ningyou ni

Hikida Reina is a bright, honor student who is liked by everyone. But her shut-in brother, Hikida Tooru, who lives in the same house, sets a terrible trap for her. Tooru's weapon is the aphrodisiac technique, which allows him to freely control his partner with a single spell. What's more, no matter how much he violates her, once the spell is over, she loses all memory of what happened. Without even realizing it, Reina's body is violated, defiled, and trained beyond repair...!

(Source: Parabook, translated)