There is a legend about Tanabata. There was a beautiful daughter living at a palace in the east of the Milky Way. She was the child of the God who ruled the heavens, but all she did was weaving, obeying her father. She kept weaving and she didn't know any girlish delights. Her strict father thought this pitiful and gave his daughter away to a youth living in the west of the Milky Way. Then, she forgot herself in the pleasure of marriage and stopped weaving. Her father finally lost his temper and forced her back to the palace. He permitted that she could cross the Milky Way to meet her husband just once in a year, on the night of July 7th.

This is the origin why it is said that Hiko Star and Orihime Star, which locates at the ends of the Milky Way, meet on the night of July 7th. "Hiko" is a youth and "Orihime" is a princess who weaves.

by Reina
Sakai, Yoko. "Tanabata." 20 Mar. 2006 <http://www.sbijapan.com/sbimag/PAGE4.htm>.