[When there are things amiss, (In-His-Head-)Detective Stilinski will be there! "There" currently being close to the reservoir, following the water with an extremely judging expression.]
No, nope, water, that's not what you're supposed to be doing! You're supposed to, I don't know, flap around on the ground and ripple and stuff, okay, not float up--
[-- which is exactly what it does, accidentally splashing Stiles on his face as it rises up, up, and then towards the reservoir again.]
Now you've done it, you little bastard, just wait until I catch you--!! [With that, Stiles wipes his face and starts to run to catch the sneaky water making its way towards the reservoir.]