Etymology and distribution of 勇磨.

Isami 【勇磨】^{レベル1
Very rare}  The Japanese surnames etymology dictionary.

Kyouto-fu Mukou-shi , Kyouto-fu Nagaokakyou-shi , Shizuoka-ken . A variant of 五十君 . The old pronunciation in estimation is Izumi. 五十君 Isogimi reference.