Secret identity FL

FL is an assassin hired by emperor, but for her work, she needs to pretend to be a dimwitted concubine who's madly in love with the emperor.

FL inherits the dukedom cross-dressed as a male by using magical artifacts. No one knows her true identity - not even her childhood friends.

That was until a mad talented guy (who was saved by FL before) came along and could see thru magic artifacts.

FL was mistaken as a S-grade supervillain while trying to fangirl a special-force police officer ML.

ML and FL later meet when FL was out of her costume. They kinda catch feelings.

But ML is dead set on arresting the supervillain without knowing it's FL. And FL feels the need to hide her identity bc ML hates the villain's guts, but likes her when she's out of costume. But theyre the same person :')

FL is actually a saint corrupted by the demon after being sacrificed for human greed. She then begins her revenge after getting reincarnated into a different body, all the while pretending to be the new coming of saint.

ML is a purifier and he's mad sus about FL bc FL reminded him of the dead saint (who was also her), but he obv can feel demonic energy.

FL acts as a maid but has been re-runing her life 4 times. She was a knight but failed to protect the prince and she restarts her life whenever prince dies.

The best way, she figured, was to be close to the prince as much as possible. And the way to do it was to be his personal maid.

Student finds out that his easy-to-bully japanese teacher actually fights in the boxing ring after school.

FL hides that she's actually a siren bc ppl coveted her singing and voice in her previous life. This life, she pretends to be mute to avoid being taken advantage of again.

FL is a sword master mercenery who hides her skills and identity.

But she gets found out pretty early by every important character in the story.

The whole secret identity is mainly a plot device to be like "yes she's strong" and surprise minor characters when they look down on FL but get face-slapped when FL starts showing her mad skills.

FL hiding her identity as the last descendent of the clan coveted for their powers using gems to obtain skills. The whole clan was executed, but FL escaped.

No one actually knows what she looks like or sounds like because she uses disguise magic all the time, meaning every individual sees a different appearance of her.

Princess FL with mad assassin skills gets sent off as a diplomatic envoy to the enemy country. While pretending to be weak and fragile, she sneaks out, only to be discovered by ML pretty early on in the story.