"Kimi ga Iru Kara"(君がいるから?, lit. Because You're Here) is the vocal theme of the Japanese version of Final Fantasy XIII, performed by J-pop artist Sayuri Sugawara and composed by Masashi Hamauzu. It is also featured in her second single of the same title.
I just composed the base of the song to let her know the musical direction, and I left the rest up to her producer/arranger. On the other hand, I arranged the BGM version of it. The song sounds like it is made by a totally different person for its usage and how the arrangements were made. The song sung by Sugawara san might not feel like my sound, but I think the song functions well in the context. I made the BGM version rather freely. I am really satisfied with it and, among all the pieces on the soundtrack, it is my favorite.
In Lightning Returns: Final Fantasy XIII, the song is referenced by Hope Estheim before he disappears on the final day when he says to Lightning, "As long as you were with me, Light...I didn't have to fear anything. I'm not scared. Not even now. Because you're here."
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