It had a great start, the village of widows and the male lead's shenanigans were very entertaining. The acting was good.
Then the romance started and things started going off the rails. While the comedy aspect was dialed down to let the narrative take a darker turn, the romance felt out of place due to its childish nature, the male lead seemed to switch personalities in the romance scenes. The main characters turned unlikeable because their intentions were so vague, especially the female lead's goal which I found so ridiculous. I even started rooting for the supposed vilain(the King) that was more interesting.

The romance consisted of miscommunication, cheesy lines that are repeated a hundred times and childish fights(i like u, wait, no i dont like u, i have to leave u now blablabla), I cringed everytime. I saw no reason for them to love eachother so strongly right from episode 4 or 5. It took too long for them to talk about their goals. By the final episode the romantic lines lost all impact because they were repeated so often. The female lead should've been the assassin lady, a more interesting character and more relevant to the plot, which would have made a more cohesive and original narrative.

And the worst of all:
Nokdu shouldn't have temporarily worked with the prince to betray the King, instead he should've dealt with the King in a different manner(because deep down he still had some good in him) but no, instead Nokdu went to live in an isolated island "happily ever after" while the King was then ambushed by the prince to start his reign of terror. What about the kingdom and its people? The fact that it ended with the prince as king was the worst ending possible, how can I believe that they lived happily ever after knowing that they left such a cruel man on the throne of the country? What if he finds out where they are?
Even if he never finds out where they are, how is a life in hiding (which Nokdu's brother hated so much and made their mother die), happy?
At least, they should've addressed them going back to that miserable life with seriousness or if it's too much too ask at least with one line or something, not with a silly half episode and the ending card "and they lived happily ever after"