this is why i hate kobe youtube link unsportman like

You would be pretty ticked off at pretty much everything that happens at every outdoor basketball court in the summer. Slapping an opponent on the rear end(or the coach in this case) isn't anything. That was Kobe's response to Alvin setting up the defense, that Kobe just shredded to pieces. Notice coach Gentry didn't look offended by it. I'm not a fan of butt slapping in sports(I almost got into a few fights over it actually), but this was harmless. If he pulled a Reggie Miller, and did the choking motion, then grabbed himself, then you would be on to something. Find another reason to not like Kobe. I suggest the mean face(that weird scowl he started doing a while back). He makes children, and puppies cry every time he does it.

It is part of the game. And I think that the action of Kobe after that difficult shot made is what we say "Competitiveness". We can see a lot of that in this coming NBA Finals.

It was a difficult shot and I do believe he was telling the coach that he had his team playing great defense. Slapping someones butt in sports is a sign of respect and saying good job.Although the timing of this slap was a little akward and can be seen as unsportsmanlike, I do not think it is meant to be viewed as such.

It is not clear for me what he did in the video, I saw nothing wrong in the video.

I don't see anything wrong in the video. They're both smiling. And we will really never know what happened unless we're near them. But based on the coach reaction I don't see any harassment in there. Its more likely that the Sun's coach was amazed. Its a difficult shot afterall.