Hiccup is studious but Jack thinks homework is boring and, like a cat, he tends to interrupt Hiccup by laying on him and messing up his papers.
Wow Demande... Way to be even more of a crazy asshole than you ever where in the anime! That reaction at having to "mercy kill" Saphir... Total contrast to how he reacted in the anime to Saphir's death and I think a perfect example of the manga and anime's handling of character's emotions. (Namely the only emotional response out of anyone we're getting so far? Mamoru, Usagi and Chibs; that's it, that's all who matters in the emotions realm!)