The Perfect Eunuch

Jang Jin-Myeong, a master of Gyuhwabojeon. He is accused of being a traitor and falls off a cliff right before he dies. He realizes his two mistakes. One is that he read the secret Gyuhwabojeon, which gives you strength but loses your masculinity, and the other is that he did not kill those cowards, Wang Jin and Seop Pyeong, earlier. When he opens his eyes in an unknown space when he is about to die, he sees the real Gyuhwabojeon and regresses to 32 years ago, just before he was castrated. Fortunately, in his second life, Jin-Myeong protects his belongings, and the power of Gyuhwabojeon still remains in his body!!! Jin-Myeong decides to go back to the choice he regretted in his past life and take revenge on Wang Jin and Seop Pyeong who drove him to death. (Source: KakaoPage, translated)