"Tales From the Cafe" by Toshikazu Kawaguchi

An audio book. I have trouble remembering names. The book has quite a few, and to add to my diffculties they're Japanese.

In Cafe Funiculi Funicula, Tokyo, customers can go back or forward in time (subject to rules that we're frequently reminded of). The boss is Nagare who has a daughter Miki. Kazu is one of the waitresses who can pour the time travel inducing coffee

To time-travel, customers have to sit on a particular chair when it's vacated (by a ghost, whose identity is revealed later). They can't changed the past, and they can only meet people who've visited the cafe. If the coffee goes cold before they return to the present they will never return.

• When Gohtaro, 51, was young he had a friend, Shuwishi Kamira. They both played rugby. Shuwishi was married with a daughter. He owned a restaurant. When GoTara became penniless they offered him work at their restarant. When the couple died in a car accident, GoTara brought up their 1 year old Haruka. Now, 22 years later, she's getting married. Goohara will have to tell her that he's not her real father. He goes back to record a message by her father to play at the wedding.
• Yukiyo, 40ish, struggled to be a potter and is going bust. He finds out that his mother has died. He goes back in time to see her and plans to stay there. She tells him to return to his time. He does so, works hard, and pulls his life around.
• A man with months to live asks a friend of his girlfriend to get the girlfriend to the cafe on a day 6 years into the future, but only if he's dead and she's happily married. He time-travels to the future and she's there. He's long dead. She's borrowed the ring.
• An old detective goes back 30 years, to a day when he didn't turn up to meet his wife at the cafe. After she had left the cafe, she died at the hands of a mugger. Having gone back, he sees her as a stranger might. She's kind to him, an old man. She confides that she thinks her husband might be breaking up with her. He says who he is. She'd suspected anyway.

Bereaved people, trying to find ways to be happy, discover that they have a duty to be happy, that they don't have to punish themselves.

Other reviews

• armedwithabook (Though the first book was more of a short stories collection since the perspective of the customer is key to its organization, this book felt very much like a novel)
• Nic Daniels (An unexpected story that was woven throughout the narrative was a subplot between Kazu and the woman that stayed too long in the past, becoming a ghost — what happens when the coffee becomes cold. It turns out that the ghost is her mother. ... Kawaguchi’s first book centered on four women who used their opportunity to shift the path of their life. They went back to help move themselves forward in the present, where they were emotionally stuck, whether out of defiance or heartbreak. Now, it’s the guys’ turns. With the men, the stories are more focused on reconciling the past and accepting it.)
• James' Coffee Blog