Looking for a novel

I've read some time ago and never finished it. I wanna read it again.
A mother remarries with a really rich man. She has a daughter she traumatizes (accusing her of seducing her ex bf, having sex with her new husband in the room next to her daughter's bedroom and moaning loudly to ensure she heard them, ...). The rich hubby has a bratty, handsome and athletic (he swims) son. The boy is an asshole to his step sister. The step daddy turns out to be weird (uses his step daughter's dirty underwear to masturbate). His son beat the crap out of him after finding out though. The parents die early in the story bc a huge fire breaks out in their villa. The kids manage to save themselves (the boy saves his step sis). The step siblings have sex with each other, maybe feelings are involved too I can't remember. The novel moved to lily on the valley before the website shut down. The novel should now be on cherrymist. cafe. If my memories are somewhat correct, there's moon in the title. Pls if that sounds familiar, remind of its title. Thanx <3