As Draco sat on the toilet, the sounds of Crabbe and Goyle bustling about outside his cubicle. He didn't realise he was about to become a victim of a failed 'Weasley Wizarding Wheeze'. He muttered to himself, about the lack of good friends, good allies. Their fathers were death eaters. But he could only see eating being in Crabbe's future, rather than powerful dark magic.
His lip curled, a sense of disgust building, neither of them were using the sinks, for a quick wash. He felt rather bloated, from the evening meal. His stomach grumbling, as it fought stretch around the extra mass. Hell, Crabbe couldn't even manage basic spells to keep himself fit. A stocky, friend could carry some threat, but now he was tending towards, podgy, or downright fat.
It was a random misfortune, that dislodged the Wheeze, from the glob of fat that held it in place in the pipe. Unattended and forgotten from the assault on Dolores Umbridges' reign of terror. As it bobbled free, it floated along, on the fetid mix of water, discarded potion contents, and a blend of unmentionable, unimaginable waste. But as it bobbed along, it started to fizzle, the pale blue paper burning closer and closer to the colourful wrappings themselves.
It exploded, as it passed the fourth floor boys toilets. A fountain of water erupting from the first cubicle soaking the ceiling. A moment later, another geyser gushed from the second cubicle. A moment after that, a shrieking, wail of protest burst from the third cubicle. Drowned out a moment after that, by the final cubicle, as a vile jet of mismatched potions and filth splattered the ceiling before dripping in loud, thick, spattering, splattering blobs to the floor.
Uniform drenched, brown, and face hidden behind a slick mask of waste, and horror. A trace of vomit already dribbling from his lower lip, adding colour to the new outfit Draco was wearing. He emerged from the cubicle. A spreading pool of grey, brown detritus widening behind him. He left sludgy, mud trails behind himself. A sickening, sucking accompanying each footstep, as he stomped, squelched towards the bank of sinks, and the wide mirror. The mirror allowing him no escape from his current state. Eye holes scooped free, allowing him a little limited view to make out the faces of Crabbe and Goyle.