I'll make it short.
I have a best friend who I know for almost 8 yrs, never go sarging with him, but i introduced him to a hot chick I know. Next thing I know they got together, and he f-closed her on the first night we hung out. Ever since then he started getting really cocky and got on my nerve. As a friend, I thought it was great that he got some, however he started to put me down, talked shit about me, trying to show everyone else that he's better than me and trying to make him out an AMOG of the grp. Any suggestion to deal with this?
Second, he's a natural, great at picking up girls, but his midgame and day 2 aren't that great. He acts like AFK after the pickup. For that hot chick, he txted her everyday, drove all the way to her place which is 15 hrs away to pick her up and drove her back, bought her clothes, pretty much paid for everything. And this chick is head over heel for him ( she does have a thing for asian). I was like wtf, he is doing exactly opposite of what I learned and she still got hooked. I wonder if it's just luck or that method does work.

destiny.

I have to go with chemistry. Or that this girl is into him because he is showering her with attention and gifts.

There are girls for every type, just because some mate walked upto a girl and said 'Im gonna take you outside and shit in your mouth' and it worked this one time, doesnt make it the next big PUA method for getting birds. I wouldnt worry about it billions of other girls out there all with different preferences.

Although saying that the most effective people ive seen with girls are the fuckers who can switch between nice guy/jerk like it's perfectly normal and know how to balance it correctly...bastards.

As for the cocky thing thats a different kettle of fish, and there are plenty of threads about dealing with it usually following the theme of not being phased by anything he says, and treating him like a yapping dog, but yeah loads more info - search is your friend!