Both had main leads that didn't get along at first. Both had misunderstood male leads. Both show a non-famous person dating a celebrity.

-male lead is a prince in both
-both have male leads with strong personalities that do not sit well with others, and are seen as a royal pain
-both male leads are extremely smart
-both couples have met previously as children
-both female leads are maiden /spinsters
-both have the plot line where should be "enemies" fall in love
-both female leads are tough and fight for themselves
-both have a best friend solider dynamic
-both have the main couples separated for a period of time
-both have dead ends for any second lead storylines
-both include assassins
-both have parental deaths
-both have an arranged/forced marriage
-extra- both have a celebrity singer acting the lead male role lol
-the "happy ending" focuses on the main couple