March Comes In Like a Lion

This is [March Comes In Like a Lion] by Chica Umino, famous for Honey and Clover. The story centers on Rei Kiriyama, who lost his entire family in a childhood traffic accident. He goes to live with his father's friend, a professional shogi player who becomes his adoptive father, and dedicates his life to shogi. After debuting as a professional in middle school, due to various circumstances, he ends up living alone in the outskirts of town while also attending high school. Through a chance encounter, he meets three kind sisters and begins to heal. It's a work that won the Grand Prize at the Japan Media Arts Festival Awards in 2011 and was also a commercial success. The manga is still ongoing, published irregularly due to the author's health issues.