Slip's Music Database: MapleStory BGM & OST Collection

Could be wrong but I thought fair use was the ability to use something if it wasn't for profit or claiming that it was your own. I could be thinking of something else.

It is, but only if the use is necessary for something other than the basic function of the copyrighted item.
For example, if you're doing a review of Maple music, you can play bits and pieces of it to demonstrate a point.
But if putting the entire soundtrack up for people to listen to for free, when the copyright holder wants people to pay to listen to it, is "fair use", then "sharing" any copyrighted item becomes allowed, and copyright means nothing.