What Is The Lump In Right Side Butt Cheek That Smells Like Feces ?

I have a lump in my right side butt chick the size of a pea, no simptoms at all, no pain, no discharch of any kind, the skind around the area its the same colour and texture of the rest ot the body, the only problem is that it smell like poo, no matter how much I clean and wash the area as soon as I touch it my finger smell as if I inserted inside my anus, what is this?, I'm a very clean person who showers at least twice a day, I always wash my butt after going to the toilet. As I said before, no pain, no discharge of any kind, no rush or puss or blood, only the smell which its driving me creazy, please help!. I'm a 54 yo male, a bit overweight with a fairly healthy life style.