There are many things that happened in the Kingdom Hearts manga that didn't happen in the actual game but for now lets just list a few.

-In the Birth by Sleep japanese manga, Ventus actually says a** when Aqua and Terra do the Mark of Mastery exam.

-During the conversation between Sora and Riku about the paopu fruit, it sounds alot like Riku wants to share it with Sora.

-Cid kills ALOT of heartless in the manga.

-Sora carries and even cries for Riku and all Kairi gets is a short hug.

-Riku also hugs Donald at one point until he falls

You can say that the MAN GAt a hard time putting stuff in the game that was in the manga and OT to get A KUoller team.

[Bane (from Batman)- When this gets published and my Wattpad career goes to ashes, I have your permission to die]