The adoption ceremony is known as sakazuki-goto (sakazuki being a small sake cup), and consists of the participants taking turns drinking from the same cup in what is originally a Shinto ritual. The kobun keeps the cup after the ceremony, both as a memento and a physical contract - it has to be returned or destroyed in case of an expulsion. The kobun may later hold sakazuki-goto ceremonies of his own and thus adopt kobun of his own. Through this method the family will grow and branch off, to the point where a new family may be formed.
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