Shitashii Kimi to no Mishiranu Kioku

I’ll come to your aid. I’m not going to give up no matter what― In his dreams, Yukinari met and interacted with a mysterious girl. He experienced a sensation of déjà vu one day when he visited a place for the first time, and there he met Yuuko, the girl from his dreams. And, to her astonishment, she had met Yukinari in a dream as well. They started to go out together in real life to confirm the phenomenon, and eventually fell in love. But one day, when everything appeared to be going well, Yuuko fainted and went into a coma….. A story about two people who have the same dream and are looking for a miracle―― (Source: Famitsu Bunko, translated)