|Big Bad Switcheroo|
|Previous Episode||The Big Five Attack!|
|Next Episode||Showdown at Fukuma Tower|
|Japanese||February 9, 2017|
|English||February 16, 2017|
Big Bad Switcheroo is the eight episode of Koro-Sensei Quest!
Class E and Korosensei have found a weird item-fetching quest when a strange force unexpectedly swaps around their bodies and minds.
The E Class have arrived to the legendary treasure in a mysterious cave in his quest. Nagisa and Karma open this mysterious chest that could make any with come true... when suddendly something weird happens... Everyone switches bodys?! . Everyone started to get very confused, suprised and crazy how they changed bodys "Taiga" ties up "Megu" to prevent is pervert acts from her original body, "Karma" and "Kaede" were sad to Megu because of Taiga's pervert acts could do, and "Tōka" was very happy to have changed bodys because she can now know what it feels to have a big chest, while "Tadaomi" seemed to have a perverted act with "Irina" trying to take his clothes. "Tadaomi" and "Megu" were both tieded up to teh top to sotop making perverted acts with the bodys, while "Korosensei", "Irina", "Nagisa", "Itona", "Rinka" and "Ryūnosuke" werein search for the magical egg to turn everyone back to normal fighting first Kunudon's blocking their way, "itona" takes care of the with his speed but slips and hurts his leg himself. Suddendly "Nagisa's" bad luck cuased a mysterious door open. "Karma" starts to worry about the others that went to search the mysterious egg and goes to search them; "Karma", "Toka", "Yuma" and the others find "Korosensei" and the others, but "Nagisa" was dressed in a swimsuit. They later find the mysterious egg and turn everyone back to normal... except for Korosensei and a Kunudon, who switch bodies.