Who is kakashis friend?

Kakashi lost many of his friends and all of his family in his tragic past, so he tends to be a bit of a loner. However, he does have a few people that could be considered his friends. He seems to be kind of close to Iruka, Jiraya, the third and fifth Hokages, and, of course, Team 7. He is also quite close to Might Guy, though they are technically rivals (more on Guy's part than Kakashi's!).

Sorry if I missed any obvious ones. :)