Tyler's eyes go wide as you pull him against you, but he hugs you bac with a wide grin. He is coming erect, and you lift him as easily as you would a child so that your cocks rub against each other. He wraps his legs around your thighs to help support his weight, and the two of you masturbate against each other. Tyler shudders and comes first with a small spurt of semen, while you feel like you are just getting started. Heat builds up, the connection between you getting stronger. You can feel his desire to be with you, the throbbing in his body.
Your own pleasure is almost to the point you are barely aware of anything else, but there is a growing heaviness in your groin that is curiously matched by decreasing pressure from Tyler's legs. And you feel enormous pressure in your testicles, heavy and hot as they swing against your thighs. You try lifting Tyler up, but his skin is oddly loose feeling, seeming to slip up with a powerful sensation of pleasure that you would swear is your own cock, except it is far too much. Even so, it takes a strange gurgling noise from Tyler before you look down.
Thick white fluid is streaming form the young man's mouth and nose, and as you continue to lift up and down, you are shocked to discover his skin is moving, but he is staying in the same position. Looking further down, you also see that his legs are gone! His body merges with yours at the crotch, and where his legs should be are a pair of basketball-sized testicles hanging low in a furry gold sheath. His arms are boneless sticks, and even they draw in and absorbed as you continue to masturbate. You should stop! You know that Tyler is somehow being absorbed into your body, that he will soon be a lion's sexual equipment.
He is still grinning up at you, a human head on the end of a swollen pink cock. Lion spunk spurts from his mouth, dissolving his teeth. He looks dazed, but very happy. But he is hardly even separate any more. As you continue to masturbate, his hair falls out, his nose closes up, his ears fade away, and his skull seems to deflate. Soon a pair of cloudy eyes and a piss slit are all that remain. You have to stop! Your brain keeps telling you to stop, but your paws continue to masturbate what is now a giant lion cock.
The eyes still show intelligence and awareness, but tremendous gushes of lion semen explode from your massive cock, each one turning Tyler's eyes milkier, smaller, until a shuddering release makes them vanish is a spray of cum. Still you keep masturbating, shuddering in pleasure, each gush splattering the walls, the floor, even the ceiling as the immense cock shrinks down to a large, but manageable size. Your testicles start to get smaller, until they are baseball-sized. A final orgasm builds incredibly strong, controlling you. With a force that makes your whole body shudder and a primal roar burst from your throat, your massive cock explodes with a firehose blast of semen and an orgasm that nearly makes you black out.
You find yourself on the floor, semen dripping from every surface in the room, the musk scent overpowering everything else. Dazed, you dimly realize that your former neighbor has been transformed into gallons of lion spunk. But not all of him, you hope. Your cock and testicles are much larger than they were before, and for more sensitive. You put your paw down to touch it, and shiver at a strange sense of awareness. The connection! You can sense Tyler. Somehow, he is still there, part of your body and yet still Tyler. No, not quite. Tyler's essence is there, but no longer truly sentient. He is aware, you are sure, but has no memory, no intelligence, no sense of self. His world is centered in your cock, no sound, no sight. Pleasure, pain, pressure, perhaps the taste of piss and cum, the sensations of the foreskin, the weight of testicles.
You should be horrified, sad for your neighbor. A young man reduced to an animal cock and balls. Instead, you feel intense satisfaction. Laying back, you let fly with a hard stream of urine that showers you with your own piss. The odors are thick and probably offensive to any human, but your lion's nostrils drink it all in as a rich aroma of you.