Really up to you if you prefer doing it in a manga form or telling it through writing it out, my suggestion is that you put both of these characters, in a story she could be a vegetarian or prefer eating people, and she can have a relationship with this guy being boyfriend and girlfriend are husband-and-wife, and go on journeys together explore the world itself.it could take place in a world called Felarya and that world there are giants is Giants nagas fairies, and all sorts of creatures that eat people, in some cases there vegetarians as well though, the story could take place there, just of my suggestion.There is a community that is called, Felarya though, here's a link to it Felarya if you want to know more about the world of Felarya here's a link to their website, www.felarya.com/wiki/index.php…