I just submitted this to Supercheats, but I figured I'd post it here to.
Red Steel has 2 different endings. Which one you see depends on your actions on the final level (Final Fight).
*spoilers ahead*
After your final battle with Toki, you will have to fight Otori. If you lose this fight and Otori kills Toki, you'll unlock ending 2. If you win against Otori (by breaking his sword), youll unlock ending 1.
Note: if you dont get the ending you want, you'll have to play through the whole game again to see the other one.