Asu No Yoichi!

A boy swordsman, Yoichi and his father stays in mountain training for his descent from the mountain. Yoichi comes to the city to lodge and stay with 4 beautiful sisters. A new more severe "training" regiment awaits him. From Wiki: After learning martial arts in the mountains for 17 years under his father's teachings, Yoichi Karasuma's father orders Yoichi to continue his training to strengthen his spirit with the Ikaruga family in the city, as he has nothing left to teach him. The current head of the Ukiha Divine Wind Style Swordplay school of martial arts, Ibuki Ikaruga, and her siblings gradually accept Yoichi as a freeloader at their dojo. In addition to domestic problems, Yoichi deals with Washizu's jealousy of Ibuki and Yoichi's supposed relationship and his school life.