7. The Killer Is Also Romantic - well both of them know each other as their other enemy in the Assassin world

8. Jenny AM PM - ml is dressing like a girl after loosing a bet ends up sharing a dorm with FL, that saw him in both identities (only started watching this so imy answer is based of the first 3 eps, though it's the main plot line. 

9. Palace Shadows: Between Two Princes (the alter ego has blue eyes)


10. The Romance of Hua Rong 


Bonus: I'm Not a Robot 


Next one can pick

10 dramas where one of the leads takes care of the other when they're sick.

1. Your Honor

2. Shopping King Louis

3. Marry My Husband

4. Falling Into Your Smile

5. Love is in the sky

6. Taikan Yoho

7. Advance bravely

8. Hidden Love 

9. My Dearest

10. Crash Course in Romance

10 dramas where one of the leads is giving "i'd let the world burn for you"

1. Hwayugi - and it was literal

2. Story of kunning palace (I mean he’s even jealous of his own kids lol)

3. The Legend of Shen Li (destroying the sea to look for her, no matter the cost)

4. My Lethal Man

5. W - Two Worlds 

6. Happy of The End

ml stabs his ex-employer for embarassing his boyfriend and also break up with his bf as not to disturb his bf's future

7. My Cherie Amour

Fl scolds her brothers, putting gum in her oldest brother's shoes, and scolds ml's brother and mother for making ml unhappy, also planning to ruining sml and sfl's wedding because she thinks ml love sfl, and she's doing everything to make ml happy including make ml's mother accepts her because ml love her mother the most.