I'm a male. My mother used to take my temp rectally. Over her knee. A lot of the time, she didn't seem to care if there were other people in the room. My brother, my grandmother, or her friends. One of whom I referred to as Aunt *****.
At the time, it was just embarrassing or humiliating. Pulling my pajamas down to my knees, exposing myself to whomever was in the room. Then, laying prone over my mother's knee, while she lubed and inserted the thermometer into my tight orifice.
She kept whispering for me to "relax", as I clenched instinctively.
It never seemed sexual to me, at the time. Though, I did experience some strange sensations.
Years later, I fantasized about my Aunt (her sister) doing it to me. Though, in my fantasies, it's clearly more sexual.
She tells me that she remembers watching my mother do it to me and becoming aroused by it.
After complaining of a sore throat, she tells me that I should retrieve her thermometer and Vaseline from the bathroom.
Like my mother, she instructs me to take down my pants and underwear.
I'm taller now, in my teens. When I pull down my underwear, I'm obviously already excited.
She tells me to lay across her lap.
As I comply, she guides my penis, so that I'm not squishing it against her. But, so that it rests against the warm skin of her thigh.
She dips a finger into the Vaseline and applies a glob of it around my sphincter.
Slowly, she inserts the thermometer into my bottom. "Relax", she whispers. Just as my mother had.
My aunt rolls the thermometer in her fingers. Twisting it in and out of me. I can feel myself getting harder. Precum is oozing from the tip of my penis.
My aunt feels the liquid touch her skin. "What's this"? She asks.
With her hand, she reaches down and feels my penis. Rubbing her fingers over the leaking tip.
She runs her fingers together. Feeling the slippery ooze.
"Looks like you're getting a little excited nephew", she chuckles.
Slowly, she begins milking my penis while twirling the thermometer in my rectum.
It doesn't take long for me to cum all over her thigh, hand and down her calf.
After, she's finished milking me, she pulls out the thermometer. "Huh, no fever". Sounding surprised.
She tells me that I can get up off her lap. But, not to pull up my pants.
She opens her robe. Revealing that she is naked underneath. She pulls me in close. She begins sucking me as she fingers herself.
I stare at her beautiful body as she masturbates while she sucks me.
I am soon hard again. More fun ensues.