You do empathize with him, your last sex was good, you know this guy for a long time, and decide, why not just give yourself a push and do him this favor, it is probably fun for you too.
Before he hangs up, you offer him "there might be something you could do", and he invites you over.
You get dressed again, and leave the house before it gets dark. You do your hair while walking. it is still unusuall to have this air between your legs in your skirt but it is fine.
At your friend's home, you greet him and he is overly excited but also anxious to appear not to be too much in need. In vain of course, you know exactly that he is desperate.
You strip down and look at his curious eyes, checking out your entire body with each step getting unclothed.
Still with your bra, tights, and skirt on, he remarks "can I have a look at your butt? Sorry, this is probably your first time too, and..."
you interrupt him "you will see much more from my butt under this skirt, because you wil fuck me from behind"
"from behind? You mean... anal?"
"You silly, you penetrate my hole from behind, you know, the girl's hole. I hope you are not too disappointed, but I am not a virgin anymore."
"You already had sex?"
"Yes"
"How was it?"
"Let's not talk about past experience, but lets create our own", you say while dropping your final clothes to the ground and take your friend to the bed, turning around and give your own butt a nice slap, so he knows what he has to do.
"And please use the right hole, will ya?"