A Transgender goes to a dominatrix

The dominatrix never had a transgender client before, but she was a professional, over 5 years in the field, so she decided to agree to take the job.

On the first day, she asked: "How should I refer to you, what pronoun do you go by?"

Trans person: "Them". And as time goes by they keep talking and getting to know each other, they even tell jokes. After a couple sessions the trans person says "Hey can you tell me that joke you told yesterday again? It was hilarious!", the dom says sure and tells the joke again, but unsure what's funny about hearing the same joke twice. They keep meeting up, having a laugh, all the while engaging in dom sex.

After a few weeks of this, the dominatrix is at a coffee shop with her friend when the trans client shows up and says hi. Her friend, surprised, asks "How do you know him?"

"They're a client" the dom replied, "but they have a weird fetish"

"What is it?" asked the friend, leaning in to hear some gossip

"This sub loves when you tell them the same jokes every day!"

Edit: consistency with pronouns