[Q] Mold in device?

This is really unusual, as I haven't exposed my Note to water (closest call was when an lcd cleaning solution spilled on the back cover)

So I took my Note out of the case and I found a white spot. I scratch it off, nothing happens. But when I smell it, it smells (oddly) like perfume. I had to use a scouring pad to get it off the back cover, but now it's scratched up. Now this concerns me since when I smell the battery, speaker and S Pen slot under the back cover it still smells like the mold on the back cover. How do I clean this?