If you like to camp but have no tent, if you like outdoors in general, then Kirei Village is the perfect place for you! Located just in front of Kirishima mountain range, this campsite has made 4 very nice rooms out of 2 big containers. There are several types of stay, single room, double room, with shower room or bathroom, etc. You can also rent a camp space if you want to bring your own tent. For more details, please check the Kirei village homepage right here: https://www.kireivillage.net/lodging/
The price range is 2,500～5,000yens per night and per person.
As for the camp space, it is 2,000 yens per night.
You will find a very nice coffee place just next door, called「Coffee Roaster Enya」and…the Cosmos onsen, very famous for the temperature of its baths (around 48℃)!
There is also a sport park (Nishimoro Forest Park) if you want to rent a ride a mountain bike or skateboard!