Exceeding limits can only be handled by reincarnated people

Story:

Each person can choose 8 "skills" for himself. People usually choose skills like Strength Gain or Fire Magic to survive in a harsh world. Our hero, Reiji, is a ten-year-old boy who works in a mine and extracts crystals with skills. Together with Lark, their named sister, they work hard. Reiji grew up to be a strong and strong-willed person, but during the riot that happened, he and Lark had to split up. He wants to see his girlfriend again. He wants to restore their relationship, and perhaps hopes for something more … This is where Reiji's adventure begins!