Sumitomo is said to have established a relationship with the pirates, the toneri (servants) of the Fugo-so (the upper class), after being dispatched to the province to replace Motona and while he was delivering tax money to Kyoto.
純友はこの元名の代行として現地に派遣されて運京租税の任にあたるうちに富豪層出身の舎人ら海賊勢力と関係を結んだとされている。