Died while saving his dear friend and cursing the arrogant general, Leo gets reincarnated into a world ravaged by magical beasts.Here, strength speaks for everything, and the weak are killed at the whims of the strong. Leo awakens as the lowest-tier Beast Master. Just as he was thinking he would again end up under the command of some stupid general who was the reason for his death last time, he received a gift from a mysterious entity.[Primordial Beast Dominion system]Now, surrounded by people who see him as a weakling, his journey to grow the strongest has begun.Where everyone is beating their head to make their beast grow and unlock their potential, Leo uses the system to break his limiter and grow fast and surprisingly strong.With dual talent, a broken system and a yandere sister, he embarks on the journey to rise at the top of the food chain.