I Hate You More Than Anyone! 9

From the creator of TEARS OF A LAMB and V.B. Rose. Kazuha Akiyoshi--a responsible girl whose free time is always filled with taking care of her younger siblings--finds herself dealing with romantic relationships for the first time in her life. Saki Sugimoto is the newest teacher at school, and he just happens to be the half-brother of Maki Sugimoto, the guy Kazuha's been getting close to. Kazuha's friend Senko really likes the newest Sugimoto, but the situation is complicated by the fact that the siblings can't stand and want nothing to do with each other. Why has Maki never talked about Saki before and what caused this bitter rift between them?