The theme of sacrifice can also be present. Maybe Astrid gets hurt while saving Hiccup, or Hiccup has to put himself in danger to rescue Astrid when she's in a hurt state. This can add a lot of drama and intensity to the fanfic.
One common theme is adventure. Since they live in a world full of dragons, many fanfics will have them going on quests or exploring new lands. Another theme is friendship. Their bond is a strong part of the story.
Another theme is family. As they are part of a community, sometimes fanfics will explore how their relationship is influenced by their families or how they build their own family in the future. It could be about dealing with in - laws or raising children.
You could also check out Tumblr. There are often fanfic writers who post snippets or links to their works there. Look for tags related to How to Train Your Dragon (assuming Astrid and Hiccup are from that), and then narrow it down to the 'Astrid Hurt Hiccup' theme.
One common theme is the overcoming of personal barriers. Both Hiccup and Astrid have their own insecurities and challenges. Hiccup's confession could be a way for them to break through those barriers and become closer. For example, Hiccup might be afraid of rejection due to his past as an outcast, and this confession is his way of facing that fear.
One great Astrid Hiccup fanfic could be 'Astrid's Discovery'. In this fanfic, Astrid might find a hidden talent of Hiccup that no one else knew about. It could explore their relationship in a new light, with Astrid seeing Hiccup in a whole different way, leading to some really cute and heartwarming moments between them.
One common theme is adventure. Since they are dragon riders, many fanfictions involve them going on quests, exploring new lands, and facing various challenges. For example, they might go on a journey to find a lost dragon or a magical item.
One common theme is love and romance. Their relationship is often explored in different ways, from the early stages of attraction to a deep, committed love. For example, in many fanfictions, they go on dates and have cute moments together.
One great Astrid hugs Hiccup fanfic could be 'The Warm Embrace'. In this fanfic, Astrid hugs Hiccup as a sign of her growing affection towards him after a dangerous adventure. It beautifully captures the emotions between them.
Hiccup would probably be very worried. He'd rush to her side immediately. He might start to check her injuries right away and call for help if needed.
Maybe Astrid is hurt while on a mission to explore a new area. Hiccup, being the caring friend he is, sets aside his own tasks to stay by her side. He could search for a rare herb to heal her wounds. As he does this, their relationship deepens as Astrid realizes how much Hiccup truly cares for her.