Okami is the right answer.
The beginning is a sore, I'm pretty sure a lot of people dropped it because of it's long intro and slow pacing, but for those that kept playing it sure is the game that keeps on giving.
When you start playing it you're playing some kind of prologue, you just don't know it yet, then when you finally kill the "final boss" and think it's the end (which would've been fine content wise), it's actually just the beginning!
Then you went on with the second act, kill all those demons and think "ok now I'm done with it", but it just doesn't end! There's more! And it just gets better!
When you finally slay the real baddie it kind of feel strange. Deep down you knew it was the end, but you feel like "That's it? Where is my next plot twist? What happens next? I need to know!". But that's it, that's the ending, there's nothing else to do except contemplate the final moments of the game while reflecting on everything you've just accomplished, specially if you done everything the game had to offer.
Now I kind of want to play it again...