He felt it when all of his bones began to melt, changing into the cartilage that shark skeletons were entirely composed of. Looking down through the water at the lower half of his body, Marco watched as his feet and toes lengthened like taffy being pulled. The transformation inched its way up his calves, until he found himself in the rather surprising position of being tall enough to touch the tile flooring in the deep end of the pool without moving from where he floated.
The sensation of something tugging at his back, something that pulled at the melting bones of his spine, prompted Marco to reach back and attempt to feel just what was happening to him. It turned out to be the sharks dorsal fin was growing out of the bones of his back. The inside of his mouth began to itch, and then something not terribly unlike teething pain dulled but recognizable began to spread through his mouth.
He was growing the teeth of the shark in his blood.
"Hey, wuss! Get outta the pool!"
Two large splashes, the sound of something heavy being dropped in the water, echoed through the formerly silent pool area. Marco turned, confronted with the two boys whod dove into the pool with him. Two particularly familiar boys: Drake and Woo; divers for the swim team, and bullies the like of which Marco made a concerted effort to avoid.
Drake was the only one whose intelligence Marco could have respected under different circumstances; Woo was an abject imbecile. They both, however, were complete and utter jerks, and unrepentant bullies.
"Get out of the pool, punk!" Woo shouted.
"Dont make us kick your butt, Marco-roni," Drake added, in what he probably thought was a menacing tone of voice.
Marco knew that he should have been at the very least worried about what these two were going to do to him, but the only thing he could find to concern himself was the possibility of them diving underneath the water for a prolonged period of time. They could, if they did something like that, end up finding out that he wasnt as normal as he looked. From the waters surface, they were far more likely to dismiss his unnaturally long legs and toes as an artifact of light-distortion.
Reversing the half-morph, Marco mentally berated himself. Hed been stupid, cocky, thinking he could get away with something this audacious in a place as public as the one hed chosen. Jake would be livid; if he somehow managed to find out. Demorphing as fast as he could managed, Marco felt his legs and toes being pulled back into his body; losing contact with the tile floor of the pool as he did so.