The Moon Flower is an item in Momodora I.
The item is just for collecting purposes and has no effect in-game.
It can be found some rooms behind the finding place of the Golden Flower. After collecting the Golden Flower, go right through an opening to reach a room with a lot of blue flowers. You can walk straight through the two rooms, since they contain no enemies at all. Like the Golden Flower, the Moon Flower lies on a pedestal in the second room.