[quote=@harinezumikouken]

<Snipped quote by MULTI_MEDIA_MAN>

Something like [url=https://www.youtube.com/watch?v=ICSk8-pJkX8]this[/url] for Oswald's theme? o3o
[/quote]

The thing about Oswald is that there's two major aspects to his personality: the part of him that refuses to sit down and take it, and the part that can't help but be swallowed by the darkness and the despair. Both aspects have been shown a bit: the former when he went rage-mode after the massacre during his mission (as well as him bloodying a good punching bag afterwards), and the latter when he shut down as soon as he saw the destruction. 

I figured out his two theme songs, actually. Both by Johnny Cash (well, one was originally by Nine Inch Nails, but Johnny made it his own with his cover, and if you disagree that's too bad because even NIN said he made it his.)

[url=https://www.youtube.com/watch?v=k2h9HPZhqHE]I Won't Back Down[/url]

[url=https://www.youtube.com/watch?v=4ahHWROn8M0]Hurt[/url]

Beware of feels on the second one. Bewaaaaarrreeeeeeee.