I'm struggling to think of more hints, I wasn't aware this game was as obscure as it apparently is! (also, no Kirin, Eternal Sonata was on Xbox 360/PS3.
Check my thread to find out more! =V)
1. There are a limited number of enemies in the game.
2. Some of them have weapons, but for the most part you fight unarmed.
3. The protagonist has...
interesting ways of getting from place to place.
4. The game is a mix of several different genres.
5. Aside from this game, the developers are probably best known for rebooting an influential horror franchise.
6. Has possibly the silliest fake money name I've ever seen in a video game
7. The game has a cliffhanger ending that never got resolved because whoops, there was never a sequel
8. The villain has two different names
9. Magic snowboarding!
10. Those are
definitely not chocobos
11. Combat plays like a fairly complex beat-em-up
12. The protagonist's mission is to rescue their brother, while also finding a way back to Earth from the weird alternate dimension they're trapped in
13. The villain is the protagonist's long-lost dad. (you learn this in the opening minutes of the game so it's not really a spoiler)
14. Your combat effectiveness is directly tied to how fashionable you are
15. You'll find yourself playing soccer a lot
16. Only ever released on the PS2
17. One of your main tools is a magic boomerang that you can eventually aim manually to hit switches and stuff. Can't use it in combat though