Jon and Karyn, together

As Karyn continued to massage Jon he could feel something strange with her hands, almost as if they were beginning to stick to him. Suddenly their clothes began to melt off of them and down to the floor as Jon felt Karyn's skin against his, and suddenly he didn't care. As the moments went on full of passionate kissing and touching the feeling grew stronger and as he opened his eyes he could see her skin beginning to merge with his own.
"Don't fight it Jon, this'll be fun, I promise" Karyn said looking into his eyes as she kissed him again, this time their lips sticking together.
As the moments passed Jon felt as her legs seemed to merge with his, wrapping around his legs and becoming a pair of silky smooth, very feminine legs. The same began to happen with his arms and hands as she skin wrapped around his, turning his into the dainty and decidedly feminine hands of Karyn, complete with long, red 3 inch nails. As the changes continued he felt his waist next being wrapped and covered by Karyn, his member shrinking in and becoming its female equivalent. He could feel his butt, and hips expanding as his waist shrank and Karyn moved up to his chest, her breasts melting and sticking to him as the rest of her body followed suit. He felt as his head was next as her skin merged with his, turning his face into Karyn's as her hair grew out, well beyond her own usual hair down to the small of her back. As the changes completed Jon stood up and looked in the mirror, seeing Karyn naked in front of it. Suddenly however he felt as if her spine began to lengthen, watching in the mirror as a long tail came out, ending in a spade. He also began to feel 2 small black leathery wings erupting from his back and as she watched in the mirror she could see her eyes change to a red color as a set of lacy black lingerie began to form around her breasts and waist, pushing her breasts up as a pair of black high heels formed around her feet.
Jon could feel the urge to find a mate, someone to help her expand her species, and later feed on. After all, what else are succubi for but to be a servant for men and their urges?