I consider myself an anilingus connoisseur, having four decades of experience with women and men doing this. One pro tip I'd love to disclose is for the person eating to slowly massage the guy's prostate with a slow gliding motion. Picture holding your finger up to move it to motion a person to come here (no pun intended, lol). A slow blowjob with lots of tongue movements along the underside of the shaft and head combined with that slow finger motion will make your man produce a very large quantity of semen that will ejaculate explosively into your mouth. Did this in a threesome with a couple and the wife demanded I teach her how to do that to her husband before I left.
Wow she's truly fantastic! Rimming is such a marvellous thing for both men and women, real moments of sharing with highly enjoyable sensations. For those who never tried don't be shy, it's only pleasure. I cannot even say if I prefer to give or to receive, I really love both.