Male Teacher/Mentor Lead/protagonist

Couldn't figure out anyway to search forums other than page-by-page.   Anyways,  Im looking for shows with a male lead who is a teacher, or mentor, or something in that sort of theme.  Preferably a decent human-being, not some jack-wagon.  Some kind of romance would be nice, but Im not terribly into the whole love triangle thing.  Maybe something with a little extra-ordinary (like in Kasuka na Kanojo, the male lead can see ghosts, and ghosts are a thing) would be nice, but thats not necessary. 

Thank you in advance for any help.

I know a few dramas more or less like that! 

Gomen ne, seishun http://mydramalist.com/10860-gomenne-seishun male teacher!

Hi wa mata noboru http://mydramalist.com/2757-hi-wa-mata-noboru I liked the mentor/student thing in this one. (I'm pretty sure I wrote a review once but it's gone from the page!)

Koukou kyoushi 2003 http://mydramalist.com/790-kou-kou-kyoushi-2003 Male teacher/student - intense and kind of twisted story but sooo good. You don't have to like what the guy is doing to feel for him!

My rainy days http://mydramalist.com/764-my-rainy-days

Taisetsu na koto wa subete kimi ga oshiete kureta http://mydramalist.com/10-taisetsu-na-koto-wa-sube...

Beethoven Virus http://mydramalist.com/135-beethoven-virus The male lead looks like a complete jerk but you'll soon see that there's more beneath the surface; there's a mentor/student romance going on as well as a mentor/student love/hate bromance! (Don't be bothered by the rating, trust me, it's way better than that! I suspect it's under rated because some fangirls like the younger guy better.)

Koi http://mydramalist.com/8320-koi it's more about the romance (love triangle but it's a GOOD one!) than the mentor/student thing though, even though that's how it starts.

Valid Love http://mydramalist.com/10874-valid-love Romance, love triangle, the male lead is a teacher but most of the drama after the first two episodes is about their life years later. (So, maybe the weakest recommendation on this list) 

Dinner http://mydramalist.com/5998-dinner The male lead is a chef who comes to help a restaurant in trouble, he's like a grumpy knight in shining armour who saves the sweet princess (the romance is very subtle and between the lines though or perhaps only in my head...)

Galcir http://mydramalist.com/557-galcir kind of weird comedy, the lead acts sort of like an alien at times but he's not... but he's acting like a kind of mentor-figure to the silly girls. Maybe you won't like it, it's very much "only j-drama can be this silly!!!"

Some other suggestions (all Japanese):
- Dragon Zakura
- Suzuki Sensei
- Yowakutemo Katemasu
Suzuki sensei is more realistic than the two others.

You may want to try Kazoku Game.  It's pretty unconventional and a bit bizarre (sort of like a psychological take on a Mary Poppins/Nanny McPhee type of story), but it's heartwarming at the same time.  There won't be much romance in it, but I didn't find myself missing it too much.