I'm not sure it's brake or clutch fluid, it looks like corrosion under the paint to me... Geez, now I have to check my bike. It's the first time here we've been made aware of this issue.
What's above that area in the photo? I don't have my bike with me at the moment so I can't look, but that bolt above the area looks as though it's doing the same thing. Is that casing magnetic or is aluminum?