Well, 'feliz cumpleanos' means 'happy birthday' in Spanish. So this graphic novel could center around a birthday - themed plot. It could be about a young person's coming - of - age birthday, with all the challenges and joys that come with growing up, depicted in the unique visual style of a graphic novel.
I'm not entirely sure as 'feliz naviad' seems like a misspelling. If it's supposed to be 'feliz navidad' which means 'Merry Christmas' in Spanish, the back story could be related to the origin of Christmas traditions in Spanish - speaking cultures. It might involve things like the celebration of the birth of Jesus, the coming together of families, and the various festive customs like having a big dinner, giving gifts, and decorating Christmas trees.
Since we don't know much about this 'feliz cumpleanos graphic novel', the main characters could be a diverse group. Maybe there's a creative artist who wants to make their birthday extra special and their friends who help them plan an amazing celebration. Or it could be a family - centered story where the main characters are parents, children, and grandparents all involved in a big birthday bash.
Since I'm not familiar with the 'Monster Dia and Meg story', it could potentially be a story about friendship between two monsters. Maybe Dia is big and strong while Meg is small and clever. They might go on a journey to save their monster homeland from some kind of threat, like an evil wizard or a natural disaster that is endangering their kind. However, this is all just speculation without more context.
Friendship is a very common theme. Since Chika and Dia have a strong bond, fanfics often explore different aspects of their friendship, like how they support each other through tough times.
The 'meg and dia monster short story' could potentially be about Meg and Dia's adventure in a world where monsters exist. Maybe they have to face a particular monster and overcome challenges related to it, like finding a way to defeat it or escape from it. It could also be about how they discover the existence of the monster and how it changes their perspective on their world.