凸でこ坊ぼう

noun

beetle-browed boy; mischief

Archaic or literary term for a boy with a prominent forehead, often associated with a mischievous or impish character. Rare in modern Japanese.

• 昔むかし話ばなしに凸でこ坊ぼうといういたずら好ずきの少しょう年ねんが登とう場じょうする。

  A mischievous boy called 凸坊 appears in an old tale.