Takakazu was killed at Mitsusuke AKAMATSU's residence by his retainers during the Kakitsu no Ran (Rebellion of Kakitsu) in June 1441, along with Yoshinori ASHIKAGA, Seii Taishogun (literally, "great general who subdues the barbarians").
いずれにせよ、高数は翌々年の1441年（嘉吉元年）6月に起こった嘉吉の乱で、征夷大将軍の足利義教と共に、赤松満祐邸でその家臣に討たれる。