Some malagasy people do the fatidra ceremony to have a new brother. For example Ikotofetsy and Imahaka were two fictive scoundrels who became blood brothers in order that one would not do any harm to the other, but it was at the end of their tricky adventures. It still exists in the malagasy culture.
You can read this article: Henri LAVONDES. Magie et langage: notes à propos de quelques faitls malgaches, Année 1963, vol 3, numéro 3, p 109-117.
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