I guess Daddi Tang really likes playing those childhood secret admirer roles.
Similarities:
- Were childhood friends
- FL moved back home then ran into ML
- FL gets hired at ML workplace as a worker that is not in the same field (accountant for software company and lawyer for hospital)
- FL has strong sense of justice/motivation
- ML is a bit cold and has many admirers but is sweet to FL

- ML and FL had childhood past
- FL has a rare disease
- ML has liked FL before
- FL was hurt by ML in school (has to do with stages)
- FL has a distinct, strong moral compass/personality
- ML is owner of FL house and lives with her (later in the story)
- both are very cute, with some drama about business competition (LIS is a bit more intense)

- ML is CEO of architecture firm and is on the colder side
- FL is assistant more on the bubbly side (but not dumb)
- ML has broken relationship with SML
- ML and FL meet through an accident

-There is a female that likes ML for a long time, is business partner, tries to sabotage relationship of FL & ML
-CEO & secretary relationship, more bubbly FL
-SML is "friends" with CEO and likes FL (at least in the beginning)
- You Are So Sweet is waaaaay more light hearted

- FL has strong family background but choses to abandon it
-FL starts working for ML
-both are comedies, although I found Royal Sister Returns to be more comedic (maybe partially bc of good chemistry)
- There is a past connecting the ML and FL and their families
-Sm:)e has a more light hearted ending

-FL is independent, smart, down to earth
-FL & ML have history (different types but still)
-has moments of comedy and more serious parts too (although WDL has more heavy parts)
-there is a kind of childish FSL

- Contracted/arranged marriage
- Slowly started liking each other
- Woman is independent/quite successful/not poor
- Is a bit involved in the acting industry

- Boss-employee relationship
- FL tries to quit job
- ML and FL has some previous history (although its different)

WBIL is more light-hearted

- FL works for competing company
- Both ML are competing CEOs interested in FL
- FL is interested in design/fashion
- Misunderstanding at first meeting

But Love Designer has more mature FL.
General storyline is different.