So in one interview Jaejoong said he doesn't write songs for any girl... Which means he writes them for a BOY & that boy definitey in from DBSK.

Well this is my own beliefs and I am not forcing you to belive me but I think he write the songs for Changmin... 

Why I think so? Well let's take the song "One Kiss" from his very first solo album...

The lyrics :

Born free, sadly, but one kiss one heart
With a slowed breath, we share one kiss
I feel it with my eyes closed in this complicated feeling
Oh I’ll try to show you
A free world

Why didn’t come my way?
Isn’t it too late?

hmm so "ONE KISS"... Whenever I look at the word I can only think of one word "ONE TOUCH".. Jae could have named his song ANYTHING... But he had to put "ONE" before "KISS" and made it "ONE KISS"... And I can't still get over the fact that Jaejoong was the one who stole Min's first kiss... and the way Changmin reacted after their kiss I don't think they would have kissed frequently... So I think when he was talking about ONE KISS it has to be his kiss with Min.. and also he said things like "this complicated feeling".. when he revealed that he had kissed Min he said that he didn't know why he kissed him... He looked like anangel so he kissed him... U can't just kiss your band member only bcz he looked like an angel... there has to be something else... I think he was referring that feeling as complicated... And also "Why didn't you come my way?"... Hmm.. I want to talk about itbut I won't because I MIGHT offenother shippers... so I decided to keep my mouth shut about it...

Why I don't think it's YunJae : Bcz YJ were too close... I am sure if they were in a relationship they wouldn't kiss just once... I know lame but as I said before its my opinion (and if U dnt agree with me its fine but don't put any YJ evidence in the comment it will be deleted at once so...)

Lyrics of I'll protect you: 

I want to protect you… even your bad habits make me smile when I’m tired
Although it may be difficult, I’m going to say that I love you until the day you first come into my arms

I can’t smile, I can’t remember even when I smile
today also feels like it may disappear like a dream when I open my eyes
Even when I see you, I feel like you aren’t with me
I guess I’m still awkward at expressing my feelings… to love you

Well the bold parts... Evenyour bad habits make me smile when I'm tired... I remember how Jaejoong always laughed whenChangmin insulted him... I am not saying it was Min's Bad habit... I am just trying to explain the hidden meaning behind tha