Tsume is the most misunderstood of all the wolves. Most people think he's a jerk, but that simply isn't so.
He's the tough guy in the Pack. Having been in a city gang. He appears to be quite irritated by Toboe, however he comes to like having him, and the others around.

[If you haven't ruined it enough for yourself keep reading - Contains Images]

[Spoiler]

Tsume to Toboe (after Toboe's death)

Tsume: You asked me about my scar once, remember? About how I got it. It's the mark of my sin.
<Flashes to a bunch of wolves being gunned down, and a young Tsume running passed them>
Tsume: I abandoned my packmates and ran as they were being killed.
<He was stopped by 3 or 4, and one of them attacked, knocking him off the cliff, leaving the mark that is now his scar>
Tsume: And I was run out of the pack. I didn't need any friends. I never trusted them. I always betrayed those around me. Until I met you huys. I wanted to take you to paradise. *very sad eyes* You were the one who brought me all this way.
Toboe: C'mon, Tsume! Let's go! I believe in you, Tsume. I won't whine anymore.
Tsume: Yeah, I know. I know. *a tear runs down & then he stands*
Tsume to Quent: Old man, take care of the runt for me. *smiles* See ya. *leaves* How does it end for Tsume?
He dies.

Does he die alone?
Yes.

What happens Spoiler-Girl?
While trying to help Kiba stop Darcia, Tsume is fatally wounded, and orders Kiba to go on without him. Saying that he's known all along that Kiba would be the one to make it to Paradise, and that he, and the others wouldn't.