Possessed but with a Messy Development

I woke up after a good night's sleep and found myself as the villainous extra in a terrible web novel. A petty villain who grinds his teeth at his half-brother's success, obstructing him at every turn, Only to fail repeatedly and eventually bite the dust. There's still room to turn things around. It's only natural to respond to a terrible novel with terrible behavior! Amnesia. What a convenient plot device. Yoo Jaehee decided to play the part of a bright, innocent, and lovable son to the fullest. But... "Jaehee." Jaehee's eyes widened at the first time he'd heard his name called. "If you have amnesia, how much do you not remember?" "Huh, what?" "Shall we kiss?" "Pardon?" "Broth...