Here's a link to a page about Hitoyoshi Ryokan:
http://www.japanholidays.com.au/traditional-accommodation/japan-holidays-ryokan-collection/hitoyoshi-ryokan-hitoyoshi-kumamoto
This is the only hotel or ryokan in Kumamoto that I could find listed on the JapanHolidays website. It may be worth considering if your planning a holiday in the area.
Hitoyoshi Ryokan - Kumamoto | Japan Holidays
DescriptionHitoyoshi Ryokan was originally built in 1934 and since that time this ryokan has refined the Japanese art of service and hospitality. The rare Sukiya style of building design will make you feel most comfortable as soon as you set foot into the Ryokan. You will enjoy spacious Japanese st...