Panties
I'm very pleased you have found something you enjoy. I have often thought that some kinds of women's knickers might be exciting for me - perhaps white cotton maxi briefs. Do you find them good for accommodating erections?
For many years now, I have been wearing unisex knickers, similar to women's maxi briefs but without gusset. Incontinence pads act as disposable gussets extending from an inch or two past my bum hole at the back to an inch or so below my waist at the front. They are usually bought by waist size rather than bum or leg hole size. This might seem questionable for knickers extending from the waist to cover the whole of the cheeks, bearing in mind the differences in relationships of waist to bum measurements between men and women as well as variations within each sex. The stretchiness of the knickers reduces the problem. I just buy a waist size bigger than might seem right, to accommodate my bum and thighs without the leg holes being too tight.