Mans butt

So when my husband gets drunk -not often- and I’m sucking him/jerking him, he’ll ask me to play with his butthole- I know this can be a very sensitive stimulating area... I just have a difficult time doing it like it feels like I shouldn’t be in that area and then like I’ll put hand under his balls so it’s kind of in the area. Am I being prude??? Do straight guys enjoy this??? Do you ladies do this for you man?? Help a sister out -tips/suggestions/advice- thank you!!!