I met this girl on reddit and she's doing weird shit

I [16M] met a girl [18F] on reddit a few months ago. She was 17 at the time, and we have been friends ever since. It was going well until now, but she recently turned 18 and things have taken a weird turn.

Now, she keeps asking me to show her my N*DES almost every time we talk. At first I said no, but she started doing things like calling me a "good boy" and "pretty boy", which made me feel kinda confident. So, I sent her a post-workout pic of my upper body (I've been training abs) and she said that she "edged to it" and that she wants to "see more".

I do not understand what she's trying to do. This whole situation has become really weird. Is she into me? Is this a sign? Should I be worried? She's been a really good friend and I'm too confused. What do I do?