Return back into the Novel as the Antagonistic Playboy

An author was reborn but it was ill-fated. He didn’t get reborn back into his own past nor was he reborn to a parallel world. Instead, he was being reborn into the world of his own novel. He was struck grief-stricken because he had been reborn as the novel’s antagonist who will soon be dead!
In order to survive a few extra chapters, he will have to become a supervillain supported by a cheat-like system launching a magnificent counter-attack step-by-step!
“Ding! Initiating primary mission: Push down the Heroine. System Notice: In view of the character’s physiological defect, a big blue bottle of tonic is being specially sponsored. Open the bottle for a pleasant surprise.”
“… … … …”
【PS1: This novel’s alternate name is : Self-Cultivation For Antagonist】
【PS2: Old crone, I’m back!】