Caught in an Abandoned Building

I really like exploring abandoned places and buildings. I also really like being naked and masturbating outoors or in public places. So it wasjust a matter of time until I discovered the thrill of exploring abandoned buildings naked!
I have done stuff like this quite a lot of times in different buildings but this time it turned out different! I drove to one of my favourite places, an abandoned terminal right beside a cycle path!
I walked into the building, searched for a good place to leave my clothes and started walking through the abandoned hallways and offices completely naked, only wearing my shoes and holding my smartphone and my mini-tripod in my hand (for taking pictures)! I started to get arroused and touch myself. Business as usual so far.
I walked into one of the big former offices where public customers would get their papers. I started taking some pictures of my naked body and my erection in all kinds of different places; sitting at a desk pretending to be working naked, pretending to be a customer and so on, while playing with myself the entire time.
This office was about 100 meters and a few hallways away from my clothes, so there was no easy way to get dressed nor really a good place to hide. I've done that quite a few times with a lot of great orgasms, often due to the risk I guess.
I was just taking some pictures from further away with the whole room in the picture when I suddenly heard steps in the hallway. My heart nearly stopped. I tried to get my phone and hide away as fast as I could!
But it was too late! The moment when I grabbed my phone a middle aged couple (the guy about 50 with quite a big stomach and a woman about 40 with quite a sporty figure) wearing biking clothes entered the room, stopping immediately and looking shocked and directly at me!
I tried to cover up my erection as well as I could, looking shocked, just shouting out: Oh f***! Sorry! Meanwhile his look had turned from shocked to wtf? and her look had turned to a mixture of shock, yet she was smiling and couldn't take her eyes off me!
As a reflex I just started running past them searching the fastest way to my clothes! After I had passed them I just heard them say: "What the hell was that?" As a result of the edging, the shock and the movement while running I started feeling the orgasm building up just when I had passed them! I grabbed my dick and shot my load all over the hallway while still running! Quite a weird orgasm!
I ran to my clothes, wiped the cum off my cock and my legs, got dressed as fast as I could and left the building! Fortunately I did not get in any trouble, and actually the thought of people catching me completely naked is still quite a big turn on!