Billion Girl

Billion Girl (ビリオンガール) (￥Juuoku Shoujo) is a shōjo manga series created by mangaka Miwa Sakai.

The first volume has been published by Hakusensha and ran in Hana to Yume magazine. Later it ran in Asuka, and all volumes (including the first one) have been published by Kadokawa Shoten.

Story
Kanoko Ooba is a 16 year old innocent girl currently attending high school. Her family owns a traditional Japaneses sweets shop since the Meiji period. When her family's company becomes bankrupt, a mysterious stranger offers to pay their family's debt, in exchange, he wishes to marry one of the daughters of the Ooba family. When Kanoko's two elder sisters refused to be married, Kanoko volunteered herself in hopes of saving her family.

Characters

 * Kanoko Ooba
 * She is the youngest daughter (a high school girl) of the old Japanese Confectionary shop "Ooba". Which is at the verg of bankrupcy. She has 2 sisters who bully her around. She marries houjo in exchange for her family debits to be paid.

He is the Houjo Family's 17th successor. He married Kanoko because of the 1 billion dollar loan.
 * Taiga Houjo

Volumes

 * 1) ISBN 4-04-924867-0 released on June 16 2001
 * 2) ISBN 4-04-924868-9 released on June 16 2001
 * 3) ISBN 4-04-924871-9 released on August 17 2001
 * 4) ISBN 4-04-924894-8 released on January 17 2002
 * 5) ISBN 4-04-924908-1 released on July 17 2002
 * 6) ISBN 4-04-924920-0 released on November 16 2002
 * 7) ISBN 4-04-924939-1 released on March 17 2003
 * 8) ISBN 4-04-924939-1 released on September 17 2003
 * 9) ISBN 4-04-924961-8 released on April 17 2004
 * 10) released on October 16 2004