I think the king let her wear the crown and sit on the throne for a bit and called it an 'experience' to sorta cover it up as a 'tourist/hospitality' thing for her when he realized that she wasn't rly trying to take over the kingdom lol ("I could leave it like that forever" is wild tho lol, but i guess at this point rona's prolly affected the country in one year than the king has the whole decade lol)
I love how this game's lore is supposed to be dark and all the bosses have sad backstories. And Rona just disrespects that and turns it into a cozy fanfic where they all get ramen together.