Anal plug is fun, men and women. Inserted part 1.5 cm for beginner, 2 to 3 cm are generally good size, 3 + cm size required more training practice.
The base( outside) part, if it is big, uncomfortable if use for long time due to its size. Choose something smaller for comfort.
Lube, inner lube can be water base lube or oil (coconut, olive or cooking oil, all natural). The the external side, perfer to use Silicone base lube, because it really last and not dry up.
Silicone plugs is soft, but if lack of lube will create more fiction. If the ractum is not clean enough, it smells even after wash/clean, but smell will go away eventually.
I perfer glass or stainless steel more.
Inflatable Silicone is also great choice. Now some of them even have a metal ball inside, it is extra bouncy. Last month I use it rubbing against my prostate, it made my prostate over excited, it takes hours to return normal. (It was near to cum, but not go pass the line)