Janus

The world is split into 7 groups called tribes. The Athens (the smart/knowledge seeking), the Pomponians (the selfless), the Somnusians (the peaceful ones), the Irisians (the honest), the Aresians (the brave), the Demetrians (the earth-loving), and the Venusians (the vain). Each person born into this society is tested at the age of 16 and is given a result of which tribe they belong in. Except for some. Some special ones don't fit in anywhere, get multiple results and are dangerous for the society. Those that are undetermined are called Janus, and are dangerous to society. They are hunted and killed if it is found out that they are Janus. They can still choose a tribe the day after testing, which is Tribe Choosing Day, and go through that tribe's initiation, but they could be found out.