httyd arranged marriage au where astrid shows up to berk fully prepared to murder whoever her husband ends up being and ruling on her own. she's got no faith that this guy is going to respect her or even be a competent leader.
hiccup doesn't want to get married, has repeatedly said so infact. very publicly said so. but stoick is worried about his line of succession and insists upon it. hiccup is praying that his future wife will want to rule, because no way in hell is he doing that
they don't have any actual interactions until the night of their wedding where, before astrid can threaten hiccup even once, he's asking her if she has any leadership experience (obviously she does). he then offers the throne to her so that he can fly off the edge of the world or something (astrid didn't quite catch what he said, something about mapping the whole world and a trader?)
this arrangement goes great, but they don't really spend any time in the same house or doing any other husband and wife things, which leads people to thinking there is some kind of weakness/tension between the two.
so someone tries to assasinate astrid.
she would've had everything under control, but before she can kill the guy, hiccup (who no-one has seen in close on two months) bursts into the room and slices the guys head off or something. hiccup then apologises for stepping on her thunder, stating that 'he was mean to my cousin, i've been looking for the guy for ages'