I don't know if these are exactly what you're looking for, but they all have the FL protecting the ML as a strong element in the drama.
Shopping King Louie - both of the leads were naive but the FL way less than the ML. She took care of him basically the whole drama. It was adorable.
Strong Woman Bong Soon - strong cute girl protects rich weak guy.
Oh My General - badass tomboy protects weak and childish husband
The Legends - The FL only protects the ML at the beginning. It's a shame cuz she's so badass initially, but they end up throwing her into the weak FL being protected by the ML for most of the drama. But man, the FL was super rad and the ML was an adorable puppy for a while there at the beginning.
Hotel del Luna - I'm not done with it but the cold FL has saved the warm ML's ass a few times already.
