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.
A mischievous boy called 凸坊 appears in an old tale.
The derivation is uncertain; the kanji 凸 (convex, protruding) and 坊 (boy) suggest a boy with a protruding forehead, but the exact origin is unclear.