According to a letter sent from Kazuemon FUWA to his father Shinsuke SAKURA, he was originally responsible for guarding the yard; however, he could not stand it and made his way into the residence where he ended up fighting against the head of Kira family Yoshimasa KIRA who was battling with his long sword.
不破数右衛門が父佐倉新助にあてた書状では本当は不破は庭の見張り担当であったが、こらえ難くて独断で邸内へ突入してしまい、邸内では長刀を振るう当主吉良義周と遭遇し、戦闘になった。