Grandma Bowser

Grandma Bowser is everyone's least favorite grandma, and is a boss in several shames, including Super Toilet Paper.

History
Although Bowser apparently has no family, Grandma Bowser claims to be his grandma. Although it is more likely that she could be Wowser's grandma. Although, that also makes no sense, as Wowser just suddenly appeared and has no affiliations, except for being Bowser's cousin. Which would mean that she was Bowser's Great Aunt. And I'm not even going to mention Dark Bowser in this.

Evilness
Grandma Bowser is evil, and hates everyone. She gets into fights just for the fun of it, and is often a very powerful boss in some shames. If you see Grandma Bowser, run for it!

Barney
Grandma Bowser was once Barney's partner, which Barney resents.

Trivia

 * Grandma Bowser has no teeth
 * Why doesn't she wear dentures?
 * She knows how many licks it takes to get to the Tootsie Roll center of a Tootsie Pop:
 * The world may never know.