The person to the left is Eragon27. These characters gave themselves code names to hide their real names from other people. Rayman136 decided to keep her name as Rayman136, as she actually forgot her true name. Whenever she is reminded of the war, you may see her break down in tears (which is not what she usually does).

If you are wondering why her horns are darker and why she has a different shirt, this is her past self. When she became alone, her horns became much darker (other than the front ones which stayed bright). Due to this, her back horns do not glow as much as the front horns do.

I tried to make it inspired off of Roblox's Ember Horns (which you can see on Rayman136's account) but I can see why it relates to that too. I think they are in a similar shape, just different colors.