I love male leads that are eccentric, or odd, or slightly overacted :P  I love when you look at a male lead and just have to stare, and maybe wonder if he's a weird alien.  The greatest love, master's sun, beautiful gong shim....that short one where he has his first crush, forgot the title....even go ho's starry night...I did actually love that one.  Male leads that are super entertaining...they don't have to be nice lol...just quirky and weird.  I LOVE beautiful gong shim

high end crush
Protect the Boss
also kill me heal me 
5-9...hero is a monk and madly in love with heroine. Kinda ott and stalkerish lol. But also very entertaining to watch. He's completely expressionless but still so interesting to watch 
high end crush, that was the other one.  Something like that.  Safae thanks for the recommendations, the other two do look interesting, and then having your recommendation for this request makes them seem more interesting.  
The Korean ones I can think of are Fated to Love youFalling for Innocence, and Secret Garden
If you don't mind Chinese dramas Proud of Love and the Sequel has a quirky male lead. 
I actually love chinese dramas....thanks Tpixie_12 :P 
** it's ok that's love **
thanks for the recommendations guys.  Funny quirky male leads are the best.  
Kekkon Dekinai Otoko (there's also a kdrama version) - I highly recommend this. Prepare for some cringe moments lol

It's Ok that's Love


Shopping King Louis
Strong Woman Do Bong Soon
adding Love Me If You Dare
dude I love "love me if you dare."  The novel is awwwesome.  and yes, exactly like that :P

Since this gets a good amount of views I thought I'd mention that the lawyer in let's eat qualifies.  He's even accompanied by sound effects.  I like to troll through recommendations for new dramas, so in case someone else does I thought I'm mention it here 

Chief Kim with Nam Goong Min fits perfect into that description. He was odd, funny and cool at the same time.