How to Use A Chastity Cage With Keyholder Pt 4

Intro
It was late morning on a Friday. I’d slept in and was just killing time at home before going to work later in the afternoon. In fact, I was cruising for some porn, getting myself worked up as I was still thinking about getting fucked by Sir’s friend a couple days ago. I was straining against my cage, pre-come leaking down my leg, when there was a knock at the door.
Fuck. I live in a highrise, so usually if someone that I didn’t ring up from the lobby is knocking at the door it’s a waste of time – people selling stuff, religious nuts or politicians out meeting the public, none of which I needed.
The knocking came again. Of course, sometimes it was something to do with the building management. I sighed and grabbed a pair of sweatpants to pull over my caged dick.
I opened the door and there was a middle-aged guy there, holding a box. Although he had a sort of corporate-uniform collared blue shirt, he didn’t look like a courier, and I wasn’t expecting anything from Amazon or anywhere else. The guy just asked my name as he clung to the box.
“Do I have to sign for this?” I asked as he lingered by the door.
“Ah, no,” he said, speaking as if he wasn’t quite sure of his words. “But, aaah… I need you to take a picture for me. For confirmation.”
With that, he fumbled in his pants pocket and pulled out his phone, unlocking it and handing it to me. As I took it, flipping it toward me to peer at the camera interface on the screen, he set the box down, undid his belt and quickly dropped his pants and underwear. He grabbed the box again. “Okay, now.”
Confused but not turned off by this turn...