I don't remember the whole thing that happened, but I remember a few years back I posted some plots I had on Facebook when I was doing that was the time. I don't remember what it was, but there was an element in it that she didn't like and called it "stupid" but otherwise wanted to roleplay one...
I finished one the same way a sad anime would.
In the middle of a shitstorm, causing a major cliffhanger.
I will never know how our star-crossed lovers got past the fact that one was totally gonna have to kill the other.
It started so calmly, and then just devolved in wonderful, exciting nonsense.
Honestly, in my opinion, the same way you do any other good character. Focus on their personality first. The reason why Quasimodo in the Hunchback of Notre Dame was loved by the audience was because he was likeable, not because he was beautiful or a cis male or straight or any of that.
I stumbled upon a Harry Potter roleplaying site when I was 12 and I've been roleplaying on and off ever since, taking hiatuses every so often.
I also used to write stories in a little notebook for fun before that, so I guess you could say it started there.