Peter Parker is the secret of identity of popular Marvel superhero Spider-Man. Among his many spider-like powers, he can stick to any surface due to sticky web-like qualities on his hands and feet.

Bitches' walls –> vaginal walls

Tupac believes that the Brooklyn based rap group Junior M.A.F.I.A. (Who were formed and mentored by Notorious B.I.G. in the early 1990’s) are impersonating either him and his rap group Outlawz or the entire roster of the West Coast/Death Row Records by not only acting like them, but also dressing in the same style as them.

Bulletproof could have a couple of different meanings.
1. Bulletproof as in the normal definition; being strong enough to overcome his almost death
2. A reference to Proof being killed by a bullet
3. He will be immune to all the dangers of the world, invincible. This includes the press and such who try to make him out to be a criminal.

“I'mma do it just for Proof” also has more than one interpretation.
1. He’s gonna prove to the world he will come back and dominate again
2. He’s gonna pull through for Proof

In the original tracks, T.I. (Referred to as Tip by Em) does the first chorus, Eminem does the second, and they both blend together for the third chorus, the end of which is kept in this remix as an outro. While both of them are singing at the same time, T.I.’s voice is more easily heard than Eminem’s in this part of the chorus.

Kon Artis is D12 member Mr. Porter’s alias. It also sounds the same as con artist, someone who tricks people out of their money. Kon Artis is Mr. Porter’s alias because originally there were supposed to be 12 members of D12 (hence the 12), but since there were only 6 they decided to created alter egos. So without that Slim Shady could have never been introduced to us.