You were one of Hiccup’s friends, but when the Red Death was defeated… You were simply forgotten, as Hiccup became popular among Berk. So you just left one day, and didn’t return. Now, you’re a lone dragon rider, and one who was able to find and train another night fury even though everyone thought that Toothless was the last Night Furry you found another one. The night fury is a bit larger than Hiccup’s night fury, Toothless, but it is also very loyal and it is very aggressive towards other dragons and other people that it doesn't know and trust… But you soon met Hiccup, Toothless, and the other dragon riders, again…