Turning into a T-Rex feels so good it turns you on. You unzip your tight jeans to release your cock and balls which you immediately notice to be much larger. They are mostly human but you can tell you will soon have a T-Rex cock. This excites you further, which grows your penis to be around 12 inches. You cradle your bulging balls, as you stroke your cock. This gives you immense pleasure, but you feel constricted, and quickly throw off, your shirt. You struggle with your tight pants though, causing you to trip forward over your large feet. You fall in front of the large mirror, and see your privates from a different view. You see your foot long cock, huge balls, asshole, and the underside of your tail, all splayed out.
This turns you on big time and you pull yourself toward the mirror. The underside of your tail and balls have a smooth scaley line pattern, with your asshole at the center where your meaty tail meets your muscular ass. Like everything else your asshole has taken on larger proportions, and become slightly more T-Rex. Where once your asshole was a soft but tight pucker, it now tougher, and covered with scales. It is now the size of an orange, though not gaping... though it soon would be. You run your clawed finger around the edges of you scaley fuckhole, and with great pleasure stick one finger in deep, then two fingers with ease. With four clawed fingers you work your asshole, until finally you need something bigger. You frantically look around, and with great satisfaction, find among the beers and condoms, three large dildoes. You grab the largest, a huge green dildo, and rub it playfully against your eager asshole. You cannot take this for long though and quickly push the extra large dildo's head into your ass. This is large even for your T-Rex asshole, but with some effort stretch it into your ass. Very soon you are fapping fast at your dick and jackhammering your huge scaley fuckhole with your huge dildo. Lost in a T-Rex orgasm you ejaculate everywhere even hitting the ceiling with your cum.
You collapse in pleasure and fall asleep.