my cat has a fair bit of this the last few weeks. she seems fine and i don't see her rubbing her eyes etc. i have never had a cat before and possibly this is a summer thing for cats? i have noticed other cats with alot of this dark stuff by her eye. i try and wipe it away but she ain't having any of it, annoyingly. i also try and comb it away as she likes to have her face combed (!), it does go eventually by her cleaning her face. i just wondered. thanks