Yandere Imouto ni Aisaresugite Kozukuri Kankin Seikatsu

Ayane loves her brother Tomoya a little too much.
Her love for Tomoya gets out of control and she ends up locking him up in captivity!

She does not want to lose him to her childhood friend Sayaka.
She gives up her virginity to him after she ties him up and attacks him.
She begs him to have baby-making sex with her in order to truly become Tomoya's bride!

(Source: Nijigen Dream Bunko, translated)