Leaky SLX brake lever


My rear brake has been leaking what I presume to be brake fluid. I can’t tell where it’s coming from. They also are requiring to be bless more often. Where my front break (that doesn’t leak) is fine and doesn’t require bleeding as often. Any ideas? I have had bad luck with rear brakes in the past so I was wondering if it somthing in my riding or cleaning possibly. Any advice is helpful.

Doesn’t show up very well in the picture.