Asu no Yoichi!

Samurai Harem: Asu no Yoichi (明日のよいち!, Asu no Yoichi!, lit. "Tomorrow's Yoichi") is a Japanese manga series written and illustrated by Yū Minamoto. It has been serialized in Monthly Shōnen Champion since October 2006 with last volume released on March 8, 2011. The manga is licensed and released in Chinese by Sharp Point Press. The manga was formerly licensed in North America by Tokyopop as Samurai Harem: Asu no Yoichi!.

It has been adapted into an anime series by AIC and was broadcast in Japan on TBS between January 8, 2009 and March 26, 2009.

Plot
His skill with a sword is magnificent but his social skills still need a lot of work!

After many long years perfecting the art of fighting, 17-year-old Yoichi Karasuma is sent down from the remote mountains where he has been raised thinking that he's going to study some new martial arts techniques... but what he's really going to learn about are some slightly more practical things, like electrical appliances, modern clothing and, most especially, how NOT to make girls want to kill you!

Unfortunately, that last lesson is one Yoichi may not survive, as his new dojo is infested with the infernal creatures in the form of the Ikaruga sisters, and they don't really seem to understand how "proper" girls are "supposed" to behave! Will Yoichi's bushido blade be struck down by the fearsome charms of Ibuki, Ayame, Chihaya, and Kagome? Or will the equally lethal girls from the rival Tsubame school be his undoing?

Official

 * Asu no Yoichi (TBS)

Other Sources

 * Wikipedia:Asu no Yoichi
 * AnimeNewsNetwork (manga)
 * AnimeNewsNetwork (anime)