The burst of paint made Katie practically jump out of her seat, coughing into the side of her arm as she waited for the fumes to subside. Strangely, before she could even get a good look at the damage the can had done to her clothes, the paint seemed to fade away, as though it had been absorbed into the fabric. Before Katie could even consider what had happened, she heard the sound of her sister's voice from the kitchen.
"Is everything all right in there, sis?" Jessi sounded concerned, though in the somewhat distracted manner of someone who was really focusing on something else. Regardless, Katie felt totally fine - in fact, maybe better than fine. There was an odd, yet somehow pleasant tingling running through her body, which she assumed to be an aftereffect of being doused with the paint. Furthermore, and Katie grinned at this, she had a secret that she could keep from Jessi. Her sister probably didn't know about the disappearing paint, and it would be fun to make sure that she didn't find out. At least for a little while.
"Yeah, just swallowed wrong!" Katie yelled back as she turned toward the couch, carefully switching the can that she held for the one that had sprayed her, making it look like the pair had slipped behind one of the couch cushions. "Oh, and sis? I'm actually not all that hungry right now, so don't worry about making me anything." While she'd just needed an excuse to get the spray can out of the room, Katie realized that upon further thought, she actually wasn't hungry anymore. She even felt strangely energized; maybe it had something to do with the tingling?
As soon as she heard Jessi's grunt of assent, the young girl quickly made her way up the stairs and into her room, shutting the door behind her. Once inside, Katie immediately got to work hiding the canister of paint, slipping it into the space behind her bookcase, sure that her sister would never think to look there. Satisfied with her choice, the 10 year old pulled one of her favorite coloring books free from its place on the shelf and after gathering together some crayons, lay down on her bed to color.
Little did Katie know that the paint she'd been sprayed with earlier was finally beginning to take effect. The young girl's body began to subtly stretch within her clothing, her torso and limbs each growing just a little bit longer, her stomach sliding against the sheets beneath it. At the same time, her clothes also began to stretch outward, her thighs, hips, butt, and chest each growing in turn. Before too long, Katie looked as though she was 12 or 13 rather than 10, her shorts now a tight-fit that only reached down to the middle of her thighs rather than her knees, and her shirt pulled just above her belly-button, a pair of small yet prominent B-cup breasts jutting out from her bra-less chest.