UK hotwife uses me as her plaything and lets me cum inside?!

When I met Kathryn, I didn't know that her husband had arranged the meeting - he must have been dreaming of a threesome with a trans woman for a long time! But Kathryn wanted to gain her own experience first and tried me out... First, she wants to suck my cock really deep and lick my ass before she rides me hard. But I'm not allowed to cum, and I'm supposed to keep fucking her! So I continue in the missionary position and exhaust myself for her pleasure - but when she finally has an orgasm, she even allows me to cum inside her!