(Yes, the following are the types of dramas I like. Yes, it is something I abhor in real life. No, I do not condone the behavior of people like that. No, I am not insane. Just FYI.)

So... Basically, I really like to watch dramas where the male lead is pretty much obsessive over the female lead. It can be a love-hate relationship, a revenge drama, a misunderstanding, just a failed courtship... if he's pursuing/stalking/courting/kidnapping her for love, (though the love can come later, it can start with hate etc.) it is my kind of drama. It doesn't have to be the main couple, it doesn't have to be the main plot, the genre doesn't matter, it can be graphic or PG, lovey-dovey or abusive, dark or funny, with happy or tragic ending, I can watch anything.

I watch Korean, Japanese, Chinese, Taiwanese and Thai dramas, anything goes.

(If anyone wishes to try recommend something, please please please do, I'd really like to watch some new dramas. But take it as a challenge... as I have watched probably 100+ dramas like this and can't even begin to list them. :'D)

 A few examples: 

A Sleeping forest (Japan)

Behind your smile (Taiwan)

Boys over flowers & Hana yori dango & Meteor Garden (Korea & Japan & Taiwan) 

Sawan Biang (Thailand)

Cruel Romance (China)

Jam Loey rak (Thailand)

Last friends (Japan)

Lady & Liar (China)

When a man's in love (Korea)

(Sealed with a kiss and Le jun kai... I did watch them. They were good, but there was no love, just abuse. I could watch more like those, but even for my weird tastes in dramas, they left me feeling horrible.)

Black prince and wolf girl
definetely: Roy Leh Sanae Rai 2015 (it's a revenge thai drama so that's that)
secret 2013 (kdrama)
Summer's Desire  --- Both lead guys are very obsessive - don't know who she'll pick until the end.
Meteor Garden ---- He is utterly head-over-heals and obsessed, she puts him thru a lot of heartbreak. (Taiwanese HYD/BoF) ... Best Director!

Sound of the Desert --- Healthy obsession, he's patient and respects her ... just passionate and a bit wild
Too Late to Say i Love You --- Anti-hero, very obsessed , good chemistry.... lots of passion.
Loving, Never Forgetting ---  He gets possessive and jealous... good story... (weak but not annoying female)

Lakorns :
Bow see Chompoo --- Very obsessed and goes crazy watching all the men around the gold-digger female lead.... sizzling chemistry.... Beware: a slap/kiss
Tangpan Gammathep (2000) --- Head-over-heals lovesick, jealous and obsessed ... she's too nice, but smart ... tho stubborn :P
Nung Nai Sueng (2005) --- Bicker and banter,  love/hate ... he's obsessed and childish, but charming .
Mafia Luerd Mungkorn: Suer --- Great chemistry, he's an obsessed lovesick puppy ... but weak writing, contrived plot.
Proong Nee Gor Ruk Ter --- Pong is great at showing his obsessive jealousy ... side characters can get very annoyingly crazy, lakorn-style, but main couple are very worth watching, especially him. .... Beware: a slap/kiss 
Scarlet Heart Ryeo Kdrama
Cubic ---Thai
Secret Kdrama
kleun-cheewit is a recent one that you might like
Last Friends ---  J-drama, has domestic abuse, obsessive, possessive, stalker .... the realistic kind, where the guy is a sicko  ...
not fantasy-land type, where he's just a misguided bad-boy and true love will bring out his heart of gold ;)
I wish his character was explored more.
99% of lakorns have a crazy, jealous and controlling male lead so you could look into thai dramas.. 
fanitha - Will check it out, thank you. 
PrettyDramas - I've seen the old version of RLSR, so might check out the new one too, thanks.
rainruma - Last friends is awesome, seen it 3 times. I've seen all others except "Loving, Never Forgetting"  and  "Mafia Luerd Mungkorn: Suer", thank you for the list. 
SooSoIsPerfection - I've seen those two, definitely plan to watch Secret, thank you.
Eunha - Thank you, I've never even heard of that one.
HappySqueak - Thanks, it looks interesting.

And TokkiLily - I know, I've watched about 40+ lakorns over the years. :D (Slap&Kiss is scary yet fascinating, this coming from a person who has watched the original lakorn, then 2 remakes of it... lol.)
Have you tried My Heart Twinkle Twinkle? The make lead in that drama is super obsessed with the female lead---not to mention manipulative and controlling.
Tara: I haven't, it looks interesting and I'll definitely watch it later. thank you :)
I was hoping this thread would introduce me to dramas previously unknown to me .... Did I really watch all the  good shows w/ this type of male character?
There must be some more Chinese and Thai dramas not suggested here ..... (C-dramas and lakorns are best at portraying these types of leads).
I know exactly what you mean rainruma! I was excited to see this thread because I really like this type of drama but it is really difficult to get some recommendations that I haven't already watched.

A few others that I thought of are two Chinese dramas:
Love is the Best
I Love My President Though He's a Psycho (what a title!)--this one is currently airing and it definitely fits the bill for a controlling, possessive, and obsessive male lead.
+1 with Black Prince and Wolf Girl

Heroin Disqualified (The Lead Female does the possessing and obsessing) 

You can also try A Million Stars Falling from the Sky