In 788, the ceremony to celebrate Otsugu's coming of age was held under the sponsorship of the Emperor Kanmu and the Emperor himself put on the crown and presented a sword to Otsugu and Otsugu was at this moment appointed to Shorokuinojo (Senior Sixth Rank, Upper Grade) and Udoneri (Ministerial equerry) and received kind treatment including 150 houses as his territory.
延暦7年（788年）、桓武天皇自らの主催によって宮中で緒嗣の元服の儀が行われ、桓武天皇の手で加冠と剣の賜与が行われてその場で正六位上内舎人に任じられ、封戸150戸を与える厚遇を受けた。