@King Tai Yeah, totally! Currently Cross and I are having a sort of cross-over with Agent in Reaper, in which they both protect different sides of the town- Agent the more business district, nicer area and Reaper the rougher, much more gang infested areas. Agent crosses over to Reaper's side, and they both end up fighting a gang, their different morals clearly evident (you'll see this if you read our posts). The thread will overall be about learning to deal with others beliefs while working with them as well as adapting to others and accepting them. At least, that's what it looks like it will be. XD
I'm not sure how you want to run with that, or whether or not you'll use Sound EFX. Really it's all up to you and how you want to fit into the story, whether it be someone in the middle ground of the two heroes trying not to pick sides when problems arise, or a hero on one of the extremes- the no killing and the always killing.
It's probably a bit more complex than that, but this is just so you get the gist of it. XD Let me know if you have any questions.