Return of the Dragon Princess
If you haven't read the story Daughter of the Dragon, go read before you reading this!
Two years after the war against the dragon hunters and after the battle against Drago Bludvist, Ash is finally free to go home. But after an attempted assassination on the dragon princess, Hiccup is reluctant to let her leave Berk for fear of being harmed. He has her stay on Berk but has a bodyguard of his choice to protect her. Unfortunately for Ash, it's someone she has been butting heads since the moment they met.