Ew

"'I really didn’t mean to turn Pretty-Friend into Purple-Friend, but I was just trying to save him from the Glitch-Friends. I hope he’s not too mad at me, because I think purple is a very good color for him. ...Well actually, I think purple is a good color for anyone.'"

Personality Description
Both as a Grimer and as a Muk, Ew was always an extremely affectionate little guy. He loves his friends and is always ready with a big slimy hug. His love for his friends makes him very protective of them, and attacking him and his friends is a quick way to earn his wrath.

Despite being older than some of the other Pokemon, Ew’s personality was quite childlike. He was unable to remember names and simply assigned everyone a nickname of “___-Friend”. This improved after he evolved, but even then, he retained some of his childlike qualities.