It is presumed that this person was either Hisauji's son or relative (Matsuoka-bon (one of manuscripts) possessed by Imperial Household Archives assumed the addressee was his son Harumitsu Odachi, but there are no records proving that Harumitsu called himself Kuro and therefore, he might be an another person).
この人物は尚氏の子弟か近親者と推定されている（なお、宮内庁書陵部所蔵松岡本は宛先を息子の大舘晴光とするが、晴光が九郎の名乗りを用いた記録は無く、別人の可能性が高い）。