Regarding the guy who shot Kelly in the beginning of season eight:
After the shooting, a detective meets with the gang to get a description of the shooter. When he gets to Brandon, he gets a detailed description of the perp and then asks: "Anything else?" Then Brandon has this look of rage and determination and says: "Yeah, if you put him in front of me, I'll kill him." And then he gets all serious like you think he is actually going to hunt him down and kill him.
Several episodes later, Brandon and Kelly run into Erica on the street and run into her pimp. Brandon starts questioning Riggs and asks him where Erika is. Then Kelly jumps in and says: "You know where she is." "You're her pimp, aren't you?" Then Riggs takes a step toward her with his hand outstretched like he's going to carress her face. In the same couple of seconds, Brandon gives him a good hard shove away from Kelly. Then Riggs pulls out a knife and says: "You just made a big mistake boy!"
Riggs takes a step toward Brandon with the knife. Brandon then takes a step toward Riggs in a menacing manner seeming to not really care that Riggs has a knife on him! That shows that Brandon is willing to give up his life in order to protect Kelly.
Not sure what Riggs was going to do but Brandon wasn't about to wait to find out!
It makes no sense that with all of his protectiveness of Kelly, he cheats on her a few episodes later!