It has also been proposed that it was not until the Heian Period that the misreading "Urashima (no) ko" became current, because names with the suffix "-ko" ("child") came to be regarded as female, even though it once applied to either gender. When the texts were written for the kyōgen theatre, the character's name underwent further change to Urashima Tarō, with "-tarō" ("great youth") being a common suffix in male names. Or perhaps the name was borrowed from who is a stock character in kyōgen.