The summer between first and second year was bizarre for Harry. The Dursleys gave him Dudley's second bedroom which put Harry right across the hall from Dudley's bathroom with its electrically heated floors.
For a while he used the toilet like a normal boy. Not that it was easy. He missed Hogwarts, and somehow his under bed peeing had become tied to that.
He'd wake in the night desiring nothing more than to crawl under Seamus's or Neville's bed and push and push and push all his urine out into their carpets. With no letters from his friends he was missing them and his routine even worse.
But at the same time, to give in would be to let Dudley win. His cousin had taken to exaggerating a sniff and expressing his shock that filthy pig Harry hadn't soiled his new room yet, tossing around estimations for how much longer it'd be before Harry's room stank like his cupboard. So Harry used the toilet. For a while.
It was about two weeks into summer when he gave in anyway. He had drunk a lot of water that day and didn't expect that his urine would cause a smell, especially not if he only did it this once. He couldn't pee under his friends' beds, but he could pee under his own. Harry crawled under the bed to relieve himself. That night he slept very soundly.
For a couple nights proceeding that he resisted the urge to do it again, for fear of the smell. The third night he was awake and bemoaning the lack of other beds to spread the smell to when it struck him that under a bed wasn't the only option. He'd sprinkled across the carpets prior to the beds and there was nothing stopping him from doing the same here. In fact, if he did all his daytime pees around the house, he could probably get away with nighttime ones under the bed without an obvious difference in smell.
This began operation scent marking. It was harder than he'd expected to try and sprinkle down the hall or in his aunt and uncle's room during the day, knowing that if they decided to come up the stairs he might not have time to hide his prick before they caught him.
The real fun was to be had when they went out. Sundays became his favorite for how predictable they were. He didn't dare risk the downstairs when they were home, but when they were out it was more than fair game.
Harry awoke bright and early on Sunday. The second the Dursleys had closed the door behind them, it was time to start. Harry unzipped, pulled out his cock, and went straight to Dudley's bedroom. He slipped his prick between two teddy bears and injected his morning piss into the expansive pile of Dudley's old stuffed animals as he watched the family vehicle pull out of the yard to go to church.
He left his cock out. Next was a trip to the kitchen for a glass of water, the first of many. He sat on the couch to watch television for roughly half an hour before he felt enough pressure to pee again. This time his prick was slipped between the couch cushions and he dribbled out what he could there.
More water. More waiting. More wetting. Harry left urine in his aunt and uncle's closet, the carpet under their and Dudley's beds, the carpet under several pieces of furniture downstairs, and was letting out tiny spritzes of pee onto the end of Uncle Vernon's bed itself when they returned home. He quickly finished up in the back of Vernon's winter jumper drawer and retreated to his room, quickly tucking his cock away.
All was as well as could be, were it not for the lack of communication from his friends. And then Dobby showed up and ruined everything.
Harry had to pee out the window until the Weasleys rescued him.
