Akuyaku no Goreisoku no Dounika Shitai Nichijou

When I was selfish and laughing loudly, I (6 years old) remembered my previous life. Is this the world of RPGs? Moreover, I am the weakest of three brothers, defeated by the heroes of the future. I am the so-called villain. How unlucky. This is terrible. I was confused and depressed, so I decided to stop being a villain first! Be a good boy, get along with my beloved brothers and servants, and defeat the death flag!!

(Source: Ichijinsha, translated)