ML doesn't deserve the FL/FL is too good for him but he works/changes himself to be better for her

I mainly prefer looking for kdramas but open to J/Cdramas. 

Examples I can think of:

He's a jerk while she's kind and caring. 

He gets poor grades while she is a smart student

He lives a poor struggling life while she lives a fine happy life. 

You can suggest other ideas that can fit what I am looking for. 

Seems like you might be looking for villain romances, ones where the villain ML has to redeem himself to the FL before she accepts him? Such as: 

• Love Better Than Immortality: best example I can think of, the ML starts out as a stone cold villain but is willing to change everything about himself to get the sweet kind FL to like him haha
• Mr. Bad
• A Korean Odyssey: demon ML is bound to human FL and has to be good for her basically
• Love Between Fairy & Devil
• Extremely Perilous Love: idk that the villain really redeems himself but he is very devoted to the FL

Some dramas I can think of where the ML is a jerk and the FL holds him accountable and makes him change before she falls for him: 

• Something About 1 Percent
• Romance of Tiger and Rose: ML starts out in a politically weaker position than the FL and he's a bad person, changes after he meets the FL and they end up in an arranged marriage

Dramas where the FL holds more social, financial, or political power than the ML, and he's either striving to become her equal or to be worthy of her:

• She Would Never Know: FL is ML's senior at work
• The King’s Affection: FL is the king (cross dressing), ML is her tutor and cheerleader lol
• Across the Ocean to See You: FL is a CEO, ML is her employee
• Be My Boyfriend: FL is popular and beautiful, ML is just a regular kid

Others that come to mind...

• Meeting You: FL is outgoing and popular while the ML is shy and has social anxiety, he relies on her to bring him out of his shell
• Assistant of Superstar: the ML is dumb as bricks hahaha and the FL is very smart
• Love with Flaws: this one is kinda complicated but the FL rejects the ML when they're kids, he spends 15 years trying to change so she will accept him, then when they meet again he once again tries to change so that she'll like him better

 Thank you for you suggestions everyone