"My in-laws are obsessed with me"
Might seem like a red flag in the beginning but i swear Theo is the greenest flag ever x3
You can read it on webtoons
https://www.mangago.zone/read-manga/a_true_knight_does_not_blindly_follow_money/
https://www.mangago.zone/read-manga/confined_together_with_the_horror_game_s_male_lead/
https://www.mangago.zone/read-manga/a_capable_maid/
^^^ this one is the MC being the green flag, like not joking this girl is the entire forest that you’re looking for
https://www.mangago.zone/read-manga/day_by_day/
^^ not historical
https://www.mangago.zone/read-manga/the_best_of_tomorrow/
^^ not historical
This is my list if you want to look for more:
https://www.mangago.zone/home/mangalist/2819024/
Recommend me romance fantasy (preferably historical) manhwa with a main love who is not only a green flag but a whole a$$ green forest. Bonus points if he gets injured or sick at any point in the story!