What I mean is not in the good way ,
Have you ever watched The suspicious housemaid? there was a man Seo Ji Hoon he loves her i think but he was scary
i don't want to spoil it if those who haven't watched it read this and also "  missing you " with harry borrison he was crazy and cant help but still love him also delicious eye candy 
My Heart Twinkle Twinkle Cheon Woon Tak was also like that spy ware on phone , always wants to know what she does but the woman was waaaaaaay to stupid and sad and naive and scared 
i mean dramas like , the guy is so in love obsessed with the girl that he kills people for her or just to be with her and stalks her 
and maybe spy's on her phone stuff like that, I also rather watch those with an happy ending ...like maybe falling in love with someone who DOES love her 
 I prefer Korean dramas, not movies,  and Japanese is fine too , 
Summer desire - the guy was very obsessive in her love (actually two of them!); now I am watching two chinese dramas with hot obsessive guys - Cruel Romance and Lady & the liar (both are great!) :)
and I forgot - Chinese mini serie (episodes are 15 min) - Le Jun Kai (you can watch on wiki). This guy is violent and mad but ollalalla... you can't hate him ;) 
A thousand years of love (it doesn't really have much of a happy ending but the guy is a crazed obsessed stalker like guy who killed her lover in a past life and when she jumps through time to the far future, his reincarnation does everything to keep her by his side. not exactly the most healthy relationship)
I would recommend  these: 

1.  Bridal mask.(Korean drama.) - Kimura Shunji. 
2. Palace: the lock heart jade.  (Chinese drama) - Yin Zhen/ 4th Prince. 
3. Birth of a beauty. (Korean  drama) - Han Min Hyeok. 
4. My delightful   girl   choon hyang.  (Korean  drama) -  Byun  Hak-Do.
5.  Goong/Princess hours. (Korean  drama)  -  Lee Yul. 
6. Perfect  couple.  (Chinese drama )  -  Liu  Wen Zhao. 
 
- All these male  characters are in their own way somehow  obsessed towards  the main girl. 
Just lemme know if i should recommend  more.  :) 
thanks a lot Ekan, your comment was useful. but i would like some character like Jae-min from what happened in bali. 
if u know some please let me know.
I would say Fashion King and When A Man Loves, but these kdramas have the same female lead.
These wtf plots are a speciality of thai lakorns
Kdrama Secret. Male lead hates her because of the situation that connects them, but as he spends time with her he begins to fall for her. Slow burn romance, but it's really good

Love never dies

Memory lost

Bridal mask

Meloholic

Manhole

Cruel romance

I guess you should try an indian drama called hasil - the guy is a psycho and he loves the girl so much and does all creepy works to steal her( has a love triangle)

Ek deewana tha- a guy who gets killed and return s as a ghost to take revenge and tries to get the girl he loved ...( Love triangle)

@keerthika are both of them Indian ?

Bashar Momin: Bashar (male lead) is a gangster who loves his sisters dearly but due to past experience (parents) has ended up as a "stone instead of heart/cold blooded" type of guy. He falls for a very sweet innocent girl who thinks of him as a brother. He does EVERYTHING to steal her and make her fall for him. This drama is my all time favourite, you can never get rid of its love sparks. 

Kuch Rang Pyar Ke Ese Bhi: i must say this is the most realistic yet fairytale drama i have scene. The guy, Dev, is a self made business man who loves his mom the most in whole world and falls in love with his mom's personal doctor. At first they break up because of their mom but THEN HIS REAL OBSESSION begins!!! this is the craziest and most addicting drama. You will also find its perfect twist where the couple reunites 7 years later after some time. If you can watch the whole drama, i promise this is exactly what you are looking for.

Sadda Haq: Oh God! I can't even express my feelings for this drama in words. Its the far most best indian teenage drama. Its about two toppers studying in best engineering university, who hate each other and compete for the first position. Eventually they fall in love and this guy is like the sexiest being on earth. He is so possessive about her. Its got season two as well and that one is bonus.

Khaani: Its about a spoiled rich bad boy who is son of a politician. One day he ends up in a fight with Khaani's (female lead) brother and kills him. Somehow circumstances lead to their marriage where she vows revenge on him and he takes her as his new stubborn mission to make her fall in crazy deep love no matter what. He is ready to throw his whole world upside down to get her in marriage with him.

Iss pyar ko kya naam doon?: Ok so this drama was one of the greatest hits, its about a bossy guy and a sweet naughty girl, Khushi, who somehow ends up in a contract for his secretary. He falls for her but one day he is told that his brother in law is cheating on his sister with khushi. For revenge he marries Khushi and now he is a crazy yet possessive lover who want to hurt her but can't stop loving her. Oh gosh, i loved it.

Rang Rasiya: A police officer saves this girl (the girl is same in previous drama, Khushi) and for her safety he locks her up in his house. She thinks he is a kidnapper or something. Watch their hatred turning into hot boiling love.

Nakusha: ok i can't take my hands of the male leads. HE IS SO FUCKING PERF.  Its about a girl who pretend to be ugly by doing all that makeup and work for this sexy attitude gangster, they become bestfriends but he misunderstands that she plot against him with his ex fiance therefore while being drunk he marries her and later her secret unfolds. Imagine how you would feel when you find your so called ugly wife is actually damn beautiful

Last but not least:

Madhubala: ok, Madhu and RK and my far most favourite couple, RK is the most popular actor of country and what no one knows is how cold blooded he is. Madhu ends up challenging his bratty attitude where he takes on the challenge and forces her into marrying him. I love the way he calls her "wifey wifey" instead of her name. He is far most intense lover. but less than Dev.


Another one, Pratigya: the girl is a very well educated daughter of a respected professor and works by the rules while the guy is an uneducated son of a gangster who is now ready to cross all limits of the world to make pratigya marry him. He is very honest at heart and passionately loves her and is very possessive about what belongs to him but Pratigya hates people involved in illegal business. How will two opposite poles attract when his obsessed love for her seems to war against her hatred for him.