She stares at it for a few moments, then she remembers. "Kyle." She hisses, suddenly falling backwards as the bus comes to a stop. She pulls her skirt down, managing to just cover the abdomen now protruding from her ass. Carefully making her way off the bus, she heads to the girls bathroom.
Standing in the stall, she pulls her skirt down to look at it again. It had a small amount of fuzz on it, but it still wasn't all that big. Just as she though this, she felt more pain, although more numbed than last time.
the abdomen grew even larger, becoming too big to hide under her skirt, or anything really. It grew faster, her ass cheeks expanding. The pain was beginning to be replaced with pleasure, and she moaned ever so softly as it finished growing. She bent over across the toilet, looking around her shoulder at it. Then she felt something weird happening to her legs. She looked down, and found the toilet becoming ever closer. She felt her legs weaken, and finally they collapsed, leaving her sitting in the stall with no legs whatsoever, and a spiders abdomen sticking out her ass. She felt more pleasurable waves begin to assault her. Her ass cheeks formed in along the side of the abdomen, fusing it to her. She looked down to see her genitalia was still female and intact, although it seems to have gotten slightly larger.
He abdomen suddenly lurched. Pain mixed with pleasure moved all along it as she felt something begin to force it's way out. She began to moan louder, although luckily no one noticed. The bell had already rung, and she was alone. There was a sploosh sound, and eight legs slipped out of her abdomen, sliding across the tiles and into the stalls on either side. The black from the abdomen moved up her body, transforming her, and coloring her skin. When it reached her breasts, they seemed to puff out a little bit, growing a second nipple beneath the first, the aerola's growing larger as well. It swam around her face, although by this point she was too deep into the pleasure of the change to notice it. A second pair of eyes grew out on her forehead, and both pairs turned blood red. Her hair turned bleach blonde, which contrasted with her blackened spider skin. She sat there on the tiles, breathing heavily as she tried to get her bearings.