Uzu Majin

The main character, Jin Hatonaka, had a dream. A boy carrying a brush as long as he is tall and his partner, a pink creature, run to escape the collapse of the "Mazin world", and the boy uses the "Mazin box" to send his partner to another world. Immediately after escaping, it is caught in the collapse and disappears. Jin had that dream many times. His grades are bad, he's always bullied, and his hard work doesn't pay off. One of them falls nearby, and out of curiosity, Jin runs to the point where it fell. What I saw there was "Mazin" with a rotary saw on his right arm. Majin in front of him launches an attack aiming at Jin, and Jin takes a rest... At that time, Majin "Kogoro", who he saw in his dream, appeared before Jin. "Why are you here in my dream?" "It's not a dream, it's a memory of my previous life."