Looking for dramas where the SML falls for the FL's false face while the ML knows her genuine true persona. Also would love it if the SML is horrified when he learns the truth. 

History: My hero - not really what you wanted but feeling is similar

Uchi no Musume wa, Kareshi ga Dekinai!! (i dont think SML ever found out tho, also "ML" and sora never really actually date, but its alluded to at the end)

Let's Eat 2 -- SML and FL both have a personality they hide from each other while ML knows both of their true personalities and somehow becomes their wingman