After Reincarnating as the Male Lead's Sidekick, I Fell for the Villain

Shi Jing had just finished reading a novel called The Villain Who Slaughtered His Way Through Everything when he transmigrated into the story as the most doted-on son of the Grand Commandant’s household, a man with the exact same name. Then... then... the legendary villainous younger brother, He Mu, actually!!! A System that appears out of nowhere, deadly assassins, confused memories, and his own villainous nature: which of them is real? Shi Jing: Which bastard wrote this novel? Why do I feel like I’ve been a major villain too?