The book's translation (apologies that I couldn't fit it all in the title) is, My Dearest, Like a Cherry Blossom.

I've not read the book but a quick online search tells me that it's a romance, with romantic master producer, Kei Haruna, leading the project.

https://about.netflix.com/en/news/new-japanese-film-my-dearest-like-a-cherry-blossom

According to the summary in the link, is probably going to be tear-jerking.

Aren't they the best kind of romance?

Rom-coms are neither romantic nor funny.