Board Thread:Questions and Answers/@comment-206.53.54.152-20140302014636/@comment-49.150.40.164-20180307125223

Otonashi died before Kanade is right but he donated all of his organs so that made him not able to go to the afterlife world yet because the people who got his organ died after KAnde's wish to thank Otonashi. so technically Otonashi was still alive but in different bodies thus after all those people dies making him go to the afterlife world to fulfill his life goal which is to grant KAnade's wish.