I always got hard during RTs. When my mom stopped doing it I have a dim memory of sneaking the thermometer to my bed and using it. I was not yet in Kindergarten so probably 5 or 6. I'd always get a little stiff boner. I was too young know what to do with it.
I found out when at my grandmas and felt ill. She told me that she was going out to get an oral thermometer because the only one she had was a rectal one she used on her horses.
I asked her if the magnificent Cornell vet thermometer could be used on boys. She said it could, but would have to be used in my bottom (schawing) and she was pretty sure I wouldn't want that and began to put it away.
I thought fast and told her that sometimes I got my temp done that way at the docs (lie) And though I wasn't crazy about it I didnt mind it much. (whopper)
She came over and instructed me to turn on my stomach. As I did, she deftly reached up and slid my bottoms down to just below my butt saying that during the enemas I'd have everything off. But having my pants tightly around my hips made me lie still and wait helplessly for the cool glass invasion that would soon be giving me masturbratory fantasies to this day.
I watched her lube the thermometer with JLube, a veterinary lubricant thats thick, slimy, and super slick.
She crossed the room where I lay with my lower half trussed like a fearful feverish Christmas turkey. I wondered if I should reach back and spread my cheeks like I did playing Dr back home.
I only wondered for a brief moment as she deftly slid thumb and index finger into my young crack and spread them wide.
She then paused for several moments, holding me open and inspecting my anus I guess.
Without warning, I felt a familiar cool wetness touch my anus. Then another pause as she asked if I was ready.
I nodded and felt the instrument violate me and slide deeply inside my eager rectum.
It felt so incredible I couldn't believe it. I vowed right then and there to never stop doing this nomatter how old I got.