A married man's regular anonymous relief

Replying to an online post [in a group aimed at gay men satisfying straight men] a man provided a picture of just his dick, explaining he wanted it taken, very discreetly; more than just anonymously.
He wanted me waiting on all 4s for him but from waist up covered ie only ass shown, with straight porn on tv and blindfolded. Keen to do whatever needed for my fetish of satisfying a straight men - agreed; opening the door and then waiting in position when he told me he was close.

Without saying anything, walked in slapped my ass, then lifting the sheet covering me slightly, slipped his dick to my face telling me "suck". I eagerly sucked him, to which he then pushed his dick right down my throat holding the back of my head to be in control. His dick quickly becoming hard as he held it down my throat briefly.
Taking it out, and moving behind me ...he pushed his dick in my ass, and starting fucking. Slowly then hard deep strokes. Me enjoying the feeling of a man in me.
A few minutes later he cum whilst deep inside, I gripped his dick with my ass to make sure I took and kept it all. He pulled out, dressed and left silently. I messaged thanking him - letting him know, would happily take him when he need to unload again. He replied "good, he had a high sex drive needed someone additional to his wife, taking his load.
Several weeks on, two to three times per week late at night, he messages wanting his load taking. Same set up each time, no much more than 15 minutes, just to use my ass to anonymously unload, getting what he needs on demand whilst giving me what I want. More he continues ...the more I want him cumming in me.