Koi Kaze (恋風, lit. "Love Wind") is a Japanese manga series written and illustrated by Motoi Yoshida. It premiered in the September 2001 issue of Evening and ran for twenty-nine chapters until its conclusion in the October 2004 issue. The individual chapters were collected and published in five tankōbon volumes by Kodansha. The series tells of the love affair that develops between 27-year-old Koshiro, and his 15-year-old sister, Nanoka.