- "That's Kroop, the mayor of Petalburg. He just babbles, whether he's alone or not. I just can't tell if he's really senile, or if he's just working that angle, y'know?"
- ― Goombella's tattle on Kroop.
Kroop lives in a pink house on the west side of Petalburg. This house is the only house in the town with a garden, and this garden offers the game's supply of Turtley Leaves. He once had a wife, but she died before the events of Paper Mario: The Thousand-Year Door and therefore is not seen, however implied multiple times by Kroop. Also, he is hard of hearing, which is why he constantly calls Mario "Murphy."
After listening to his stories, Kroop tells Mario about Shhwonk Fortress. He also elaborates on how Hooktail has the first Crystal Star and his held up in his fortified castle on the other side of Petal Meadows.
Kroop also has the trouble "Listen to me!", in which Mario must listen to him tell a long story. Afterwards, Mario obtains a Turtley Leaf.