The MC already has a strong background at the first part of the story. I remember she crossdresses and becomes somewhat like an imperial advisor to the country with many talents and skills in martial arts, politics, medicine, etc. And ML is some kind of prince that has weak background and there are many assassins after him. The MC and ML are also childhood friends and MC has a debt to ML's mother so she tried saving him. ML then wants revenge after being kidnapped by the assassins and MC helps him. The MC is kind of a righteous person, but she doesn't shy away from killing people. She's morally principled. While ML is somewhat blinded by his hatred and thirst for revenge after being betrayed and hurt many times since his enemies killed his mother and tried to kill him too by sending assasins. They make a very complex yet interesting pairing. The novel is pretty good and the first time i've seen in historical romance where ML and MC actually depends on each other instead of just the overpowered flawless ML always saving the day, the sad thing is it's very underrated and not a lot of translators care about it. It only has few chapters translated till now.
Ahhhh I think I have read this one before… does the mc friend with a prime minister? He’s also in love with her and stop her from saving ml and his mother?
YES There's also the part when the ML tried to poison the lake near a village so that his enemies who owns that village would die. But the MC stopped him because she doesn't want him to dirty his hands by killing innocent people who also lives in that village but the MC was willing to do it in his stead so that the responsibility and guilt would pass onto her instead. That part made my eyes tear up so much but I just can't find the novel anymore.