Higurashi When They Cry: Time Killing Arc, Vol. 1 — Ryukishi07

When the minister of construction minister's grandson disappears amid protests against the dam project in Hinamizawa, detective Akasaka is sent from the Tokyo Police to investigate. Posing as a tourist, Akasaka becomes fast friends with Rika Furude, and the little girl almost makes him forget that he's on a mission to find a kidnapper! But the sightseeing tour takes a sudden turn when Rika delivers a grave warning: Leave Hinamizawa...before you come to regret it...