Her AB boy has a nasty diaper rash and running a temperature. His carer rubs soothing lotion on his bottom and balls and right up his bum crack. She needs to check his temperature so places him over her knee and inserts a large rectal thermometer in his bum hole.

She leaves it there for a while, moving it in and out and rotating it. Her AB boy is thinking it feels rather nice. Finally she pulls it out and, yes, he does have a bit of a temperature.