the WN ended with a platonic-harem ending (because Katarina was oblivious to everyone's feelings even in the end).
When the story got adapted into anime and manga, the LN was extended and Katarina kinda ended up with the prince (her fiance) I believe. However, and this is just a rumor I read somewhere, the author plans to do all the "routes"? Honestly imo, the series should have been left open-ended so that people can ship whatever the hell they want.