[quote]You're right about that, there's no rule about when your characters must have lived, there's no say that they have to arrive in the after life at exactly the same time of their deaths.

Actually, it's even in the anime when you think about it, since Otonashi arrived at the Afterlife after Tenshi and this should be impossible if he arrived at the time of his death, 'cause of spoilery reasons that you know, right?

Don't read this if yo haven't watched the anime [-]
Kanade had his heart for some time before she died, so it means that he must have died way before her. However, she's the oldest one in the Afterlife on the anime, which is probably a few years of time before she even met Yuri for the first time, there's a novel that confirms this[/quote]

That may be because Spoiler.

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Otonashi was the original programmer who turned himself into an npc after his first love interest was reincarnated. 
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