The heroine is a girl named Kotone who inherits her grandfather’s cafe after he dies. Upon entering it, she looks over the entire cafe having nostalgic feelings coming back from when she was young and lived with her grandfather. She then finds a strange room with “staff only” on it. When she enters it, she finds a huge extravagant door that has a “closed” plate next to it. After changing it to “open” an other-worldy man appears and says he finally found her and embraces her closely while telling her he’s been waiting for her.
I know this game is coming out in English, so you can use my skip to non-spoiler thoughts if you don’t want to spoil anything.