Tbh I like the idea of a Eret, Astrid, Hiccup love triangle. But triangle as in. Astrid and Hiccup are the only ones in the relationship and Eret has the utmost respect for the two of them and protects the two of them at all cost. So the two of them get scary dog privileges but Astrid is also like a scary dog in that she will take care of Eret now that he is proven redeemable and that means that Hiccup has two scary dogs. Coz let's face it he is basically a kitten even by the third movie.
Yeah :}