Book 5 tackles the specific topics of rape and HIV/AIDS. I have only read book 5 of this series, but I am glad that author drew out the situations into manga format, therefore allowing more young adults to understand these perhaps taboo or misunderstood... things.
This manga has reinforced my beliefs that anime and manga are not only for little kids. It isn't always about a kid saving the world with superpowers or a flowery romance story about a couple in high school; there are series that tackle the dark, taboo issues of today's society. Thank you Reiko Momochi-san, for opening my eyes.