Personally, I think that life exists because it can, and it's goal is to remain existing. I don't think there's any real "meaning", unless you count if you believe in other-worldly beings creating life as experiments.
I know that Roxas came after Sora, but this just surprised me a little.
And they don't look similar, they look EXACTY the same, save for clothes, which are even similar. They even both have checkered wristbands. Funny how before this, I only ever saw his face.
Alright, here're the ones you'll need to go and check. I crossed out ones that I know for sure can be checked in your journal.
1 - Finish Atlantica. 2 - Finish 100 Acre Wood. 3 - Chest at the Brink of Despair in the World That Never Was.
4 - Clear the Goddess of Destiny Cup at Olympus Coliseum. 5 - Chest at the Sunset Terrace in Twilight Town. 6 - Chest in the Central Computer Area at the Space Paranoids.
7 - Collect one of each of the other 49 materials. The Moogle give you an Orichalcum+ automatically.(Did you re-talk to the moogle?)
You know how in TWTNW at the top of the castle where the door appears? (forgot name) Roxas joins with Sora THERE, not in twilight town.
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In fact, just watch the part from where roxas is in the virtual computer room to where sora comes out the pod, and it doesn't necisarily say what you said.