At doctors office - examin and enemas
"I'll have to test your obedience and your anal capacity - how much you can take anal". I had no doubt that it was my Master who spoke to me. In the room next door, he picked up a cart with a large selection of dildos and butt plugs in different sizes - small, medium and large and in different designs. I lay here expectant, exposed and tense as he stood drinking his coffee while looking at my ass and my testicles.
"Spread your buttocks !" - I thought the next thing I should notice was a butt plug but instead a syringe with a long tip which left an appropriate amount of cool KY. My ass buttocks were still sore after spanking so I barely felt the first butt plug. Their size / length was increased each time one was changed and for each butt plug he ordered me with his usual tone to squeeze. "I can check if you do as I say" so I obeyed of course.