Mast Cell cares more about living the life of an otaku than he cares about the necessities of life, uses a smartphone too much and develops straight neck. When he goes to a chiropractor recommended by Memory Cell… for some reason he turns into a baby again!? Having a tiny body again, he remembers important things he had forgotten. Amazing! He’s working! He’s giving it his best! Volume 5 of the popular spin-off which you can enjoy no matter where you start reading from. You just might end up learning something while you’re at it.