So, he got outside on the roof that was accessible also for all other inhabitants of the house. It meant that any of them could visit the roof at any minute to have a smoke, for example. This open-air terrace has been created specially for leaving tobacco smell out of flats and offices, and for rare romantic parties.
The knowledge that doors may open in the most unexpected moment, even if in fact all other tenants are busy or at work, forced him to odd acts that could lead to embarrassment or even danger. Besides that, the lock on the roof door was placed on the stair side, so if anyone would want to close it by chance or from some strange desire, he’d have to stay on the roof till morning while some smoker would have a wish to have a taste of fresh air.
In fact a possibility of a real trap of a situation was more of a soulful fantasy, so his main purpose was a game with an Unknown Watcher. This person must have a name, you know. To give him any fictional name is to make himself a fiction. And what if he really does watch from a window across the street, staying silent and invisible, or peeks from a downstair office when staying a last person on the floor? He has a name already, and it would be egoistic to give him a fake one, like a dog tag, and be dissapointed if meeting him in person…
No, we’ll let this subtle connection stay a flurry touch, not an invasion and conquering, all more so premature and false. This kind of people are called stalkers as usual, but only if they suck up to your life by themselves. Here we have another angle: he was showing and offering himself gods know to whom, he suspected that this kind of behaviour teases and taunts, but he never really believed in the actual result.