Yoake Mae yori Ruriiro na (夜明け前より瑠璃色な, Yoake Mae yori Ruriiro na? lit. "The bright blue light before the dawn") is a fictional series centering around a princess from a kingdom on the moon who lives with a family on Earth for a time. It began as a Japanese adult visual novel video game developed by August that was first released on September 22, 2005 for the PC, and the PlayStation 2 adaptation developed by Aria was released on December 7, 2006. A manga, illustrated by HoeHoe Noumiso began in Dengeki Daioh magazine on September 21, 2005, and a 12-episode anime based on the series, called Yoake Mae yori Ruriiro na: Crescent Love, aired in Japan from October 4 to December 20, 2006.

Source: Wikipedia