Asking for verification, is that normal?

Hey all. I'm quite new to this world, and posted an advertisement yesterday trying to find a SD. I got a reply this morning, and the supposed SD asked if I could verify, I said ok!

He asked for a new selfie and I sent him one, and then he asked "Lay on your stomach with your legs up and take a selfie to show that’s you baby girl." He wanted me to show the soles of my feet in the photo, too.

I thought this was a very weird ask, and way too lewd for a verification picture, and I said as much to him. He said "you have several photos of you naked on your profile, how is this too lewd when you won't even be nude?" and I told him it's about the pose. He insisted, and I asked him to send me a reference of the pose he wanted, because maybe I wasn't understanding. He refused, and said I was "too fucking stupid to understand what he meant". That's when I blocked him.

What I'm trying to understand now is, is that a normal thing to ask? I think the selfie was quite normal, and if he wanted a full body photo of me with a crumpled piece of paper or something, I would have said yes. But laying up and showing my feet seems too specific and too kinky.

What do you guys think?