HELP--Smelly, dirty bottom (short hair)

I apologize in advance for the gross and graphic nature of my question!

My recently adopted cat Gretta (1 year) doesn't clean her butt. She has lots of poop around her anus and it is really gross. She has short hair and almost no hair around her bottom, so it's not an issue of it getting caught in her hair. It's really a problem b/c there is such a strong odor when she is sitting on my lap or just sitting near me on the couch...sometimes I have to move b/c the smell makes me feel sick.

I've kinda have tried to clean her bottom with a wet paper towel, but to no avail. she usually gets away and the paper towel is clean (no residue).

I'm pretty sure that it;s not her anal glands b/c my previous cat had major problems with hers, which I had to deal with on a monthly basis for her entire life.

Any suggestions (besides bathing) that will help clean her off?
Thanks!!

No advice other then maybe call the vet and ask about it or maybe take Gretta for a checkup just in case?

You should get her checked by a vet to rule out health issues, but also examine what you are feeding her, and why it might not be agreeing with her. If she is obese, she may not be able to get back there to clean herself. Adding an exercise program of interactive play every day will help. If the stool is hard, she needs more water, so start her slowly on canned food and add water to it a bit at a time, if it is loose then she needs more bulk or fiber in her diet. You can give cats one of the following with canned food to put more fiber in their diets:

mashed and cooked green beans with a bit of butter
a little bit of organic loose leaf catnip
metamucil
canned pumpkin (uncooked)