Thread:Monollama/@comment-3024153-20181025055136/@comment-28245851-20181025062742

A far more detailed summary can be found on the Hope Arc page, which is "technically" the 12th episode of Despair Arc and serves as the conclusion to the series.

To recap Kyoko's status: In a previous episode of Future Arc (I don't remember which one) Kyoko finds the bottle of medicine Seiko had made to try and save Daisaku. Kyoko knew that she had a time limit because of her NG code so she took the medicine right before (we don't see it, but it's told to the viewer later) her timer ran out and she was poisoned. The medicine slows down the effects of the poison, and put Kyoko in a "coma-like" state as opposed to killing her outright. So Mikan was able to fully revive her when she came across her after her and her classmates came to the building. After that, Kyoko worked with the other survivors to rebuild Hope's Peak.

I hope this answered your question. :)