You suck that cock with every fiber of your being, laving lovingly along its pulsing length. The tensing and quivering is familiar to you. He's about to come.
[PUT A SPOONFUL OF CUM IN YOUR MOUTH. CONTINUE TO SUCK THAT DILDO. HIS COCK HAS EXPLODED IN YOUR MOUTH. FEEL THE TEXTURE OF THE CUM. FEEL THE RAW SHAME AND DELIGHT OF BEING A CUMSLUT.]
He fills your mouth with sticky hot cum. You continue on, knowing there's more to be had. Your slut mouth is coated with semen. So is his cock. You lick it clean and gobble down extra drops wherever you can find them. Swallow.