Y'all seem to interpret the question way differently from what I think of when I hear it. There's being comfortable with your skin, which I see as almost entirely separate from being comfortable in your skin (Which may have nothing to do with skin at all). I grew up as a child of the internet, spent many of my days interacting with people on forums, in games, via IM, and through IRC. As such, "talking to people" meant the same thing as typing to them at odd hours of the night. School and family were, to an extent, a distraction from this other world and during The Formative Years I lost somewhat of my ability to straight up talk to people, like openly, with proper communication, and all that jazz. So when I hear: "are you comfortable in your own skin?", I'm reminded of those days when I was happiest as a virtual creature and I avoided the ephemeral world, where my skin no longer did not exist. Because I was by and large not comfortable in my skin in that world, I practically leaked anxiety and discomfort. I didn't know what to do with my hands, with my eyes. My back would curl forward and my legs would tense up. No matter that I was not fat (I was closer to skin and bones, but my concern over this wouldn't arrive for another few years). Nor that I was tall (but not too tall). First and foremost, I did not appreciate the idea that I had skin at all, and was not simply a program, a routine, that could interact with words via words and keep to the depths of the web in peace, not having to think about how long to make eye contact for or how firmly to grasp the skin (or do you grasp muscle? or bone?) when performing the handshake function.
This describes me. Right now it's 01.51 in the morning and I'm dreading having to socially interact with people - even though I'm good at it - or rather I'm skinny and white, short and a redhead so people think I'm cute. Even when I am actively panicking people think I'm cute. People don't DISLIKE me, they just instantly treat me as a manic-pixie-dream-girl without REAL feelings. 'Cause I'm cute. And fun. And younger than everyone.
You know, it took me way to long to realize why people suddenly started being so goddamn nice when I was 13. Not just boys, everyone. Teachers, girls random people I'd never met before. I had been bullied up until then, and people who had treated me like I didn't exist were suddenly looking at me. I freaked out. i had no idea that it wasn't because they hated me until I met new people who hadn't known me before.
That is honestly the thing I love most about the internet, and using text to communicate. You can't see what other people are, you don't know who they are, and nobody knows who you are. All the bullshit that exist in real life that revolves around who you are disappears in an instant, and nobody is able to judge you for anything but what you say. It's also why I hate seeing chat becoming popular in games, I want to keep the world where it's all text, and all... humanless?