Transmigrated as a Third-Rate Villain in a Doomed Novel

[Warning—18+] [HAREM]!!! [NO NTR] [NO YURI] !!!----------Karl was your average human being with a normal problem—he was a NEET.Even though he had this dangerous disease of staying at home. He was capable enough to take care of himself.Well, he didn't have another choice.However, the universe didn't even like this small happiness filled with a shitload of sadness of his, as he was transmigrated—not as some grand person or overpowered character, though.Haha… No. How could he have an easy life?Karl...He was transmigrated as a fucking minor villain in a doomed novel.