A voice called from the entry way. "Will?! Are you here?! We have a party we're supposed to be getting ready for, or did you forget?" Megan entered the living room, her eyes going right for you. She started, her head quickly turning away. "Oh! I'm sorry! Are you Will's guest, I was just looking for him."
You're confused for a moment, how can your girlfriend not recognize you? Then another glance in the mirror brings your mind full circle. You barely look like your old self at all, almost nothing left of the scrawny hairless runt you were before, now a muscular hairy figure of masculinity. You turn back to her, "Megan, it's me, Will."
Megan turns back to you, shaking her head, then looks at your face. Most of your features, while more rugged, still seem to be yours. "You do look like him.." She comes closer, to get a better look at your face. She places one of her hands on your chest, fingers resting in the dark hair on your chest. Her nose flares as she inhales deeply, shuddering as she exhales. "That.. smell.. so musky." She presses her face between your pecs, taking another deep breath through her nose. You place your hands on her shoulders as she slowly lowers herself, running her fingers through the fur on your chest then stomach as she goes to her knees. Her hand grips your larger cock, already hard from your own stroking from earlier, only harder now from the contact.
As she places your cock in her mouth, beginning to run her tongue along the shaft, tickling the glans your eyes drift back to the television. Your heart stops for a minute as you see the scene on the TV. The hot muscular werewolf stands before another man on his knees, sucking the werewolf's cock. You shiver as Megan hits a sensitive part of your cock, but still your eyes stay glues to the screen. The werewolf howls as he comes into the man's mouth. The man falls back, gripping his sides as he begins to grow fur and turn into a werewolf. The scene, and the feeling of the blow job proving too much for you, you throw your head back and moan as you cum into Megan's mouth, sucking as if she needs to catch every drop. Once the orgasm fades she pulls back, licking her lips and looking up at you. She lets out a small groan as she sprawls out on the floor, writhing slightly, making sounds half pain, half pleasure.
Her tight shirt gains some slack around the chest as her breast begin to shrink, vanishing into a flat chest. A bulge begins to form under her short skirt, tenting the loose fabric, until it falls back, a large erect cock stick up from her crotch, panties pushed down by the throbbing organ, a set of testicles growing from under the cock. Her body begins to enlarge, her waist growing outwards, a short ripping noise tearing the skirt, the useless fabric falling off, the panties following shortly. Her expanding shoulders make similar work of her shirt and bra. Laying there on the remnant of her clothes, you can't help but think she looks like a rather thin man, not the woman she is.. or was. Her body so similar to the one you used to have, scrawny and mostly hairless, except for that huge cock, almost a match for your own. Her face starts to become more masculine, her features getting thicker, jaw becoming more square as her lips thin.
The muscles on her thin body begin to grow, miming your earlier growth. Arms and legs thickening as he chest pushes out into a pair of pecs, abs becoming defined on her once flat stomach. Soon her body looks athletic, not like your own body builder physique, but muscular none the less. Her pale blond pubic bush thickens, becoming a darker shade of blond, similar colored hair growing in a quick spread on her arms and legs. The curly blond hair grows up her abs, fanning out on her chest, circling her hard nipples. Stubble grows along her jaw and chin.
The changes slow down and finally stop, everything about her now masculine. She, now he, runs his hands through his own dark blond chest hair, tugging on it, hands going down to feel his new cock. His eyes look to you, his deeper voice sounding odd to your ears, but fitting this new man in front of you. "What did you do?! This feels so good!" You smile down at your boyfriend, your cock stirring to life once again at his hairy athletic body.