Sorry, there's no Mac version of Fruity Loops. You're only option is to run it in Boot Camp or Parallels. I haven't used Fruity since version 5, but from what I remember it runs pretty light so it might run fine in Parallels. That's just pure speculation on my part though.
If you're not familiar w/ it, the 'closest' DAW I can think of is Propellerhead's Reason, although truthfully they're still pretty different. They have a demo available to try out. You can use Reason's redrum, it acts like a step sequencer but it's really the same as your normal piano roll like any other program. It's a great program overall though.