"Call me daddy"

Cecilia • Mom x2 Nurse
So, there has been a lot of people on here saying that they love it when they call their SO daddy. 
I have always been to scared to call my bf daddy. He's asked me to before and I tried and I just couldn't make myself do it. I want to, just to see what it's like lol but I'm just scared or something! 
Have any of you called your SO daddy? And did you like it, or was it weird?