Looking for dramas where the male lead falls first and possibly they have a one sided crush for a very long time because they don't confess. The male lead doesn't always have to act shy, maybe he is just around his crush? Also, he gets visibly jealous but not in an overly aggressive way, more like a cute and pouty way. I don't know, is this too oddly specific? it's more like a jumping off point, feel free to rec me anything that even loosely fits this. Male lead's crush can be male or female, I'd watch either. Also, if at all possible, a happy ending. 

The Romance of Tiger and Rose - Shy and adorable when he is alone with the FL, slow romance but great plot and acting. (Not a long time crush)

My ID is Gangnam Beauty - He's known her for a while and longer than other people in the University, he's quite shy around her.

Introverted Boss 

I Cannot Hug You  - Has a second season. ML is shy in general but FL gets him interested because of how outgoing she is. (Not long time crush)

Come and Hug Me 

Sweet Combat +1

I'm not sure if this is what you were looking for :(

The Romance of Tiger and Rose +1

Put your head on my shoulder