My Possessive, Chaste Brother Has a Skin Hunger for Me

[Faux-sibling dynamic + skin hunger + instinctive attraction + obsessive, twisted, gloomy ghost of a man who forces his love on her + flirtatious dog-trainer heroine and seemingly sweet but secretly dark personality + simmering tension + strangers in public, intimately familiar in private] From the first day Song Junyue moved into the Chu household, she knew Chu Qingyue hated her. But she had no choice but to live under the same roof as him. After all her efforts, their relationship finally began to improve, and she thought that meant he might come to like her. As it turned out, Song Junyue had succeeded. He did fall for her. Chu Qingyue stopped resisting her touch, and the two of them grew closer and closer. Until she discovered everything he craved. One day, Chu Qingyue learned from his father that a younger sister would be coming to live with them. His father told him to take good care of her, but Chu Qingyue didn't want a sister and hated the idea of her, until the moment this so-called sister appeared before him and everything changed. He discovered that she held a fatal kind of attraction for him... I hate it. I hate that I'm not your brother. If I were, no matter what happened, I would have every right to stay by your side forever. But I'm also glad. Glad I'm not your brother, because then I can be more than just your brother. Come close to me and you'll fall. Stay away and you'll suffer. Embrace me and you'll sink. Watch me from afar and you'll be lonely. I'm so despicable that I actually hope you'll suffer just as much as I do, so when I plunge into the abyss forever, I'll see you waiting at the bottom. Note: They are not related by blood, and both are adults.