So I just came back home after eid, pulled the cover off the cars and noticed this absurd patch on the CL's trunk. Tried scrubbing it out with soapy-water, failed miserably.
I washed the car properly before covering it - though I did use a new-cover for it, used the same cover for the Civic as well didn't notice anything odd on that car.
No idea wtf this is, anyone here with any similar experience - help a brother out.