Silly me, at first I thought it was going to be a romance novel, according to the title and the Japanese love-oriented way of writing. The idea conveyed here was way more interesting - a housekeeper who comes to work for a math professor, whose brain was damaged in a car accident, with the consequence that his memory lasts only 80 minutes.
I was sure I would love this novel, yet it turned out to be quite boring for me, as it was filled with accounts of baseball games, which didn't interest me in the least (in Romania we don't have baseball and, anyway, I would be bored to death watching sports). There is also a great deal of math lessons, presented in a pleasant and easy-to-understand manner, yet only a couple of them aroused my interest for mathematics, and not by much. A mathematician baseball fan would surely adore this book.
What I liked, though, was that I found out a bunch of interesting facts about my birth day number, 28. It is called a "perfect number", because the sum of its divisors is also 28 (1+2+4+7+14). It can be also expressed as the sum of consecutive natural numbers: 1+2+3+4+5+6+7=28.
The story which transpired through all these lessons was quite a good one, which is the reason I could eventually finish the book. Too bad it was buried under layers and layers of boring stuff.