Erasem

Erasem (Boukyakku in Japan) is a small yet deadly monster accidentally hired by King Dedede in the episode "Escar-Gone". It is a small creature that, once entering the brain of a host, can give off some sort of weak brainwashing wave that make everyone around the host forget who he or she is. However, unlike most monsters that Dedede orders, she attacks Escargoon instead of Kirby. As a now agonized Escargoon wanders the streets of Cappy Town unnoticed and unrecognized the next morning, it soon becomes evident that Erasem's power is to make her foes disappear from everyone's memory, leaving them alone and forgotten about. Luckily, Kirby is somehow able to see Escargoon for who he is (perhaps Kirby's uncontrollable brain power made him immune to memory loss), and offers him some small comfort. He is also able to convince his friends to help free him from her ghastly presence. The gang uses a torture machine located in the castle's basement in an attempt to expel the monster, which is the only way to free him from her clutches. Escargoon is eventually freed from her possession and Erasem threatens to posses someone else. Erasem swiftly floats out into town, but Kirby inhales her. The town now has no recollection of Kirby (even including the iris transition at the end of every episode, which aimlessly searches for something to close in on), so he spits her back out soon after. Before Kirby has the chance to destroy Erasem, she disappears, exclaiming "Bye bye Kirby!", never to be seen again.

Physical Appearance
Erasem is a tiny (nearly microscopic), pale, insect-like monster, and also appears very ghostly. She has a large circular head which is roughly half the size of her body. She has a lone, small horn sticking out of her head and very small arms. She has tiny, thin eye holes, and is often seen traveling in a bubble when not inside the body of one of her victims. Erasem is also one of the few female monsters from Nightmare Enterprises. She is also one of the few known monsters who can talk, similar to Slice n' Splice and the transformed Lovely.

Trivia

 * When Escargoon is pain stricken and realizes he has been forgotten by all of Cappy Town in the Japanese version of the anime, the ending theme for Revenge of Meta Knight can briefly be heard in the background as he desperately looks for someone who remembers him.
 * Erasem's name is a portmanteau of erase and them.
 * Erasem's Japanese name, Boukyakku comes from "Boukyaku", which is Japanese for "forgetting" or "memory lapse".
 * In the episode "Scare Tactics - Part II", Erasem can be noticed inside a siren in the glowing-light room. She is hard to notice and does not play a role in the episode.