According to the "Heike Monogatari" (The Historic Romance of Taira Family), a sake bottle (called "heiji", the same pronunciation as "the Taira clan" in Japanese) fell over when Narichika stood up and when Goshirakawa asked, 'what was that?' Narichika answered, 'the sake bottle (heiji) fell over,' and when Shunkan asked what to do with it, Saiko said 'we must take its neck (kill)' and broke the neck of the bottle.
また『平家物語』によれば、成親が立ち上がって瓶子（へいじ）が倒れ、後白河が「あれはいかに」と問うと成親が「平氏（瓶子）たはれ候ぬ」と答え、俊寛がそれをどうするか尋ねると西光が「頸をとるにしかず」と瓶子の首を折り割ったという。