Rear Seats are wet

Ewwy they're wet with this brownish stuff. I don't think i left my windows open or n e thing. It's the rear seats only on the right side. I dunno why its so wet!!! I tried paper towels and a regular towel but its still there. Any suggestions?

Spray your car with a garden hose and check for leaks... Otherwise maybe its just a soda spill.

done, no leaks - prolly soda

steam clean it with one of those little steam clean vacs. see if it happens again