Heart of Loyalty (2021)

Both dramas are rather light and genereal historical setting is simillar. Both are about females that travell to the city and become investigators and then fall in love with their partner in solving crimes.

Historical, Detective, Smart Female Lead, Nice Male Lead, Romance, Adapted from a web novel, Marriage, Slow Burn Romance, Palace Politics, Investigation, Smart Male Lead

Historical, Detective, Smart Female Lead, Nice Male Lead, Romance, Adapted from a web novel, Marriage, Slow Burn Romance, Palace Politics, Investigation, Smart Male Lead

historical costume drama. both about an investigation into the secret organisation. both about politics and the royal family. the big bad in both is in a high position in the government and can`t be touched by ordinary means. both merge action and romance well.

Same actor as ML who has a similar personality. Similar tone and a lovely strong relationship between the mains. Both are relatively short dramas that never become boring and have happy endings.

Both are lighter toned mystery/romance dramas with a stoic ML and a cute, endearing FL solving cases together in historical China.

Two couples, both with happy endings and their own interesting storylines. Similar tone, setting, and length. Sweet and mostly upbeat plot.

Both are lighter toned mystery/romance blends with a similar vibe and relationship between the main couple.

Mystery/historical/romance genre with the main couple working on investigations together.
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Similar tone, historical setting, sweet romance with a happy ending. Similar length and a light, breezy watch. Likeable SML.

Mystery/historical/romance genre with the main couple working on investigations together.
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Similar setting, length, tone, and characters. Happy ending. Mostly light watches with a few serious moments.

Both are mystery/romances that start out with a bickering/semi-antagonistic main couple.
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Mystery/romances with initially bickering/mismatched couple.
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In the early episodes of RFY, the relationship between the main couple is very similar to the secondary couple in HOL. The FL vs. SFL are princesses being forced to marry a prince of another kingdom, and the ML vs. SML is a guard of lower status who initially refuses to admit his love for her despite fighting and risking his life to protect her.