Geez, those who compared this series to a hentai must not have read beyond two chapters.
The first chapter is indeed a bit shocking, as the author may not have fully decided yet what the tone of the series should be. However, the tone becomes considerably tamer right after, and what we're left is a charming series about friends and family, set in a multi-racial world that has overcome most prejudices and is working on overcoming more. You discover this world little by little through its news and legislation, its history (previously filled with racism) and stories. I chuckled in particular at a fairy tale that Hime reads to her little sister, where after the hero destroys the evil wizard, he writes a constitution, and everybody lived happily ever after under a fair democracy. This is a world where people have wondered if their history would have been less violent if they were not all so different.
This theme about overcoming racism is further explored when a representative of the little-known reptilian race gets sent to the school. They quickly clear up misconceptions about one another and learn to get along despite their huge cultural differences. Outside this little town, however, not everything is so harmonious, so we discover the ongoing issues and efforts in the politics overseas.
Most of the series focuses on the characters' everyday lives, however, as they meet up with friends and take care of their family. It is a charming little series where their differences make their lives more interesting instead of creating conflict.