Something like 
-Doctor Stranger 
-My love from another star 
-My girlfriend is a gumiho
Every suggestion is appreciated :)
(It doesn't have to be just Korean Drama)
pick any old k-dramas rom-com, almost all of them has a jealous girlfriend

- Goong / princess hour
- lie to me
- full house
- shining inheritance
- you're beautiful
- my girl
- smile, donghae
- sweet 18
- warm and cozy


My  Love Eun Dong :D There is one girl who is really in love with the main protaganist, and there's a guy who is really in love with the other main protaganist. But both the main protaganistes are in love with each other!