Pushover Extra Trains the Villainesses

Somehow, the protagonist Kim Jin possessed a rich pushover extra in a novel who was exploited by the villainess and then met their demise together.

But there’s no way Kim Jin would let that happen! He immediately defeated the villainess and locked her away. After that, the only thing left was to steadily enjoy life in this world while investing and extracting profits using his knowledge.

But why… the more he punished her, it seemed that the villainess he had captured began to cling to him too much?