From MangaToshokan:
This is a story of fairies, told in a place without a name. Once in every 100 years, a young fairy from in the deep bush must come to the human world to become an adult. They use 'power' to attract a human male, to fall in love with. Afterward, the man dies. But, the fairy to whom he'd given his love will grow wings and become a beautiful adult.

This fantasy romance story starts off with a fairy of Grass, named Grassbee, going to the human world to become an adult. Will she be able to attract a human male? Will she be able to become an adult fairy and get fairy wings? Magic can only do so much...

From: Easy Going Scans

Among humans they were called wizards or witches.
For the 'Wolf Tribe' they are called 'The Contractors of the Moon'.

For the wolf to obtain 'Moonstream' it must form a contract with an existence between the 'physical world' and the 'eternal world'. The wolf gains great strength to defeat any foe in its way.
For the human, is an opportunity to achieve one's goal, together with eternal life!