Evil/Bad Guy/Villain Falls In love female lead?

Are you still there? 

Drama : Money Game

Eugene Han (the villain) x Lee Hyejoon (the heroine). 

He's insane I think, bcs he tried to hurt her in the first place for things didn't happen as he pleased bcs of her. He took a picture of her when she's not looking. 

He's violent, manipulative, mommy-obsessed, & creep. He literally talked about his mom whenever he's with the heroine. 

He's the head of Bahama Bank Korean branch. He obviously have a "mission" to do, in which harms/affect the FL's work.

She's strong willed ordinary civil worker. Principle above all else, no matter what others perceived of her, she doesn't give in any emotions. 

He talks about money all the time whenever he open his mouth. He valued people by their salary.

The thing is, he opens up only to her. He talks about his sad life only to her. He speaks softly and tries to help her family who's in financial crisis. That being said, with everything that he is, loving money ain't a crime. He asked her to come to him and make her value (salary) 10000x.

The drama has 4 eps left. Idk where this is going, so...m

The Take of Nokdu

As you've mentioned, the female lead is tough and has a backbone and there are a lot of scenes with her and the villain.  Even though, overall other plot points are given more focus in the show, the villain is obsessed with her enough to want to keep her by his side even if she would never love him. However, he does let her go in the end, so I'm not sure if this fits what you need or not.

Apologies if some of these have been mentioned:

Turkish:

Serifin kizi- Villain in love with lead. I personally can't stand this drama because the villain rapes her the freaking hero refuses to believe her and thinks she had an affair. Really makes you wonder who the hero is( still airing)

Zemheri- the villain also falls in love with the lead. And he's ALOT more charismatic than the hero. Actually rooted for him here(still airing)

Korean Drama:

MIni drama- Failing at love. Not so much the hero. But someone the rest see as a psychopath is in love with the lead

 Take me away:

Never said he was actually in love with her but he was pretty obsessed with her.

Then what is the point of posting it here? The op is asking for that troupe and this drama doesn't have that. A drama that has that would be something along the lines of Love in Darkness- THAT'S a proper bad guy obsessed with the fl. The bad guy in Voice said the fl was different in literally one episode and that was it. Some else suggested My Mister and even that suggestion makes sense because even the the bad guy isn't the ml, his obsession of the fl and how he treats her matches what the op wanted. But hey, this is just MY opinion. Op could watch Voice and completely agree with you.

I have a really similar recommendation for you. Fittrat. It's an Indian web series.

The female lead, say, H is a gold digger but only really cares about her best friend. The male lead (who is also the villain of the show) falls hard for H, but, he is H's best friend's fiance. He gets really obsessed and does everything in order to get H, he's also a powerful person, but H never gives in to him, in fact, she hates him. He even sabotages her friendship with her best friend in order to get her. It totally fits your style. The way the show ends is also amazing. The male lead is yummy and has acted really well.

Born Again (ongoing)https://mydramalist.com/54921-born-again

Born Again” tells the story of a detective, the detective’s lover, and a serial killer who loved the detective’s lover. Although their lives ended 32 years ago, death became a new beginning for them when they reincarnated into a prosecutor, a bone archaeology instructor, and a medical student, rekindling their twisted fates once again.

Chaloey Sak

FL starts out dating/in love with villain 2nd male lead,

but when she realizes gradually through falling for the ML instead,  that the 2nd ML is EVILas hell, she starts to dismiss him & stand up to him.

If you can stand her being a bit dismissive at 1st to the villain, I highly recommend, the ONLY reason she doenst stand up to him & stay away yet is because she's unaware if his true nature. Once she becomes aware she is the ONLY female in the lakorn who stands up to him lol   (the rest of the females are total psychos & idiots who want to be with him despite him being evil mistreating them & even when he tries to rape or kill them, those idiot females still obsessively want to be with him).

I recall the ending being a happy one,    but before it,  expect FL & ML start out as enemies, and FL and her brother mistreat ML at first as a revenge (family feud),   a playboy rapist killer 2nd male lead,  many psycho obsessive women who are viling to manipulate, poison and even kill babies just to be with the 2nd male lead evil guy, even when he doenst want to be with them (he wants to be with FL) & even when he tries to kill them and they know he's a rapist, and even after he tries to/rapes them.