From the Super Mario Wiki
“Oh man, this town is just plain JUMPING with ladies who are just my type!”
Slim is a resident of Flopside in Super Paper Mario. Throughout the game, he is in love with many different women, such as Tinga and Merlee. During the prologue before Chapter 7, he is in love with Nastasia. After the end of the game, he says that he met Nastasia, but her heart still belonged to Count Bleck.