Poofessor's Backstory: he was the beloved teddy bear of a nerd, when he was find out by the school bully and ripped and thrown to a toilet (which explains why Poofessor looks like a teddy bear and has both reference to school and poop)
Tongus's backstory: She was a small, poisonus mushroom who had the strange circumstance of only being poisonus if it was licked. Kids in the town that the mushroom was in would dare eachother to do different things to it to test what poisons you. One boy had the misfortune to be dared to lick the mushroom. The boy died shortly after. Out of guilt, the mushroom became Tongus, making it her goal to go around the world and heal those in need a repentance for her terrible inccident.
Kantaro was a tin can that was well loved by a boy. One day, the boy and the can met with an accident and tragically left this world. The boy's spirit merged with the tin can and Kantaro was born.
Backstory for Life-Is-Parfait:
She was originally a pudding in a shop. The pudding was made with the shop's carefree daughter. However, she was never bought and beacme a yo kai after the shop closed down.
Backstory for Brushido:
Brushido was a foot soldier during the warring states period in japan. He was well known for getting places clean in a flash. He fought and gave his life in the battle of sekighara.
Backstory for Grainpa;
Grainpa was a humble worker at a rice mill. One day, he was working at the mill when he was forced out of it to make way for a cake factory. His rage turned him into grainpa. He liked the mill and never left it, causing teh cake shop to eventually close down when everyone he inspirited when to eat rice