I think I love Toothcup so much because of something I read in a fic...
Hiccup basically saved Toothless's life, they hang out all the time together, they eat together, sleep together, play together, etc....From an animal's (Toothless's) point of view, they're mates. And I mean that in the humpty-dump way, not the British slang way.
Which is why Toothless should be anthro'd (either into a strong and silent type since he can't speak Human, or with a similar body type as Hiccup...still silent, obvs) and absolutely smitten with Hiccup.
Yeah. I've put a lot of thought into this. I'm a fanboy.
