I got pretty close to an independent escort I've seen the last 3 years, and still today.
She liked me as a customer, and gave me her personal number, and would always accept seeing me even when she stopped working.
She once changed her personal phone number, and remembered me enough to text me to let me know of the change.
She's great because when I'm feeling horny and needing something right away, she would make herself available, very reliable.
A few times, she would have her boyfriend over at her place, so I would offer picking her up, driving her to my place, and driving her back. So I'd get an extra 20 minutes of caressing and foreplay on the drive to my place
Funniest experience was when I texted her, feeling desperate for a blowjob. She told me she was at a party at a friend's place, and that we could take a room if I didn't mind her friends.
I went for it, and she held my hand and we went straight to the bedroom while she presented me as "this is my friend" and everyone gave me grin and her best friend said "you lucky boy".
I couldn't help myself as she gave me a blowjob, with grunts, and moans, and dirty talk. When I came, I could hear giggling outside, and then absolute silence and smiles as I walked out of the appartment.
I'd say this is the closest I've been to "befriending" an escort.