Have some fun as you lay in wait

Carrying her up the stairs, you place Susan down on her bed before heading back for a moment. Despite your size, you manage to clean up most of the mess your mating had produced in the living room, even if the smell remained. Lights were turned off, doors and windows were locked, and all seems normal as you return to your mate to await the arrival of her daughter.

Susan soon adjusts to her new center of gravity, her muscles rearranging themselves much like Amy's had to better fit her new role. Mooing with continued desire, she kneels down in front of you in the darkened room to grab your re-hardening cock. She pushes the tip past her lips before it grows too large, swallowing hard to get as much of the length down her throat as quickly as possible.

You can't really believe what you're seeing, her throat visibly bulging as your cock reaches full thickness halfway in. Despite what both she and Amy could take into their pussies as well as Amy's remarkably accepting ass, this was not something you'd thought of. You throw your head back and growl low in intense pleasure as her throat begins to squeeze and suck on you, her hands pulling at your waist to get you to step forward. Slowly but inexorably, your entire length disappears into her mouth as her lips press to your groin. You can feel deep inside her, and you're pretty sure the head is right at her stomach as something in there is tickling the head with every contraction.

She gazes up at you with those same deeply loving eyes, unbelievably happy to be the one to put that look on your face, and moves back and forth. About half a foot moves in and out of her mouth as she sucks hard, moving faster and with ever more enthusiasm as you put your paws on her head. She moves her hands to your balls, massaging them tenderly, and you can smell her own arousal growing ever greater. The idea that fucking her mouth gives her the same pleasure as fucking her pussy turns you on even more.

After maybe a minute, you try to pull free. She didn't seem to be struggling, but there was no way she couldn't need to breathe. When she quickly grabs your fur to pull you back in, trying to smile and sign to you that she is fine, the ludicrous idea that she might actually not need air right now dared to find itself the only real explanation. Slowly you push back in, your cock growing even bigger and pressing into her stomach as you do. "I'm liking this mishap more and more" you say, grinning lustily. Susan's eyes seem to giggle in response, her thrusting and sucking growing again.

For several minutes this continues, her saliva coating your cock as you piston in and out of her throat with abandon. Each bottom out reaches her stomach, but you do not feel the discomfort you thought you might as more possible alterations are hinted at. You're left with only one real conclusion at everything you've seen with Amy and Susan: whatever mistake happened, it not only causes the animalistic transformations and the incredible sexual powers, but it also turns your mates into perfect partners. Both you and any you mate with change so that you can give and receive ultimate pleasure. Weak human flesh is simply unable to cope, but the new bodies can give and take it in spades.

As all this sinks in, you begin to feel your orgasm rising. Again and again you thrust the cowgirl against your crotch until at last she first goes rigid and then shakes in another massive orgasm. It takes every ounce of self control to hold back, but what you wish for finally happens. Your knot grows within her mouth, her eyes bulging out in surprise at this turn of events.

With a complete seal, you finally let loose with a reluctantly restrained howl. The torrent of cum floods past her jaw, firmly locked on your bulge, then down her throat and finally into her stomach. You see her eyes roll back as a second orgasm hits, the thick streams of your cum adding to what she had swallowed before. You feel her tits and bloated belly press into your legs as she takes on weight, her stomach eagerly taking in all you have to offer. She sucks vigorously the whole time, the rippling of her esophagus milking you as best it can. The bulging pushes both pairs of her tits upwards, adding an upper dimension to her bloated belly.

As you watch, however, you can see the bulge reach a certain point and then pulse up and down with each new gusher. It takes nearly a full minute, but the volumes you are sending into her slowly taper away and the shrinking begins to win out. By the time your knot deflates and you are able to pull out, she seems only slightly bigger than she was beforehand.

Pulling you out of her mouth, Susan lets the still thick cum dribble on to her face. With her leaning back to get her face under the tip, you notice that your first summation was not entirely correct. Her tits begin to grow again, only instead of seeming to reach new sizes they appear to be filling. Thin streams of milk find their way out of her straining nipples to confirm it. You are momentarily distracted from them by a renewed growth in her pregnancy, her belly gaining another 6 or so inches atop its already massive size. Susan moos again, this time in a bit of discomfort, looking up at you pleadingly.

"M-Master...please drink from me. My tits are so full for you, they hurt. Your sperm is so wonderful it not only let me make so much to feed your lust, it made our babies grow faster, too! Master needs to have plenty of cum for when Tami returns. Please, take pity on me and replenish your strength with my milk..." The adoration for the effect you had had on her is plain, as is the real need for relief. Without further ado, you lean her back and began suckling fervently. You are again greeted by rich streams, Susan mooing thankfully with every suck.

Another question enters your brain as you do so: How were either of you able to make so much? It seemed the amount produced far exceeded any estimation of the amount put in. The spell again seemed the only reason. The ramifications of whether or not there was a limit didn't have time to stay long before the both of you hear a car pull up. The sounds of footsteps are clear to you even up here, and you hear every movement as Tami unlocks the door and quietly walks in.

Susan sighs through her enjoyment, softly speaking up as the sounds downstairs continue. "Should I call her up here, Master? I'm feeling much better now, so you needn't worry. Whatever you want me to do to help you breed her, I will do it."