Ame ni Kieta Himawari

Nara Kenichi is a police officer who is tasked to investigate the disappearance of an 11-year-old girl, Ishioka Aoi. It is not known if she was abducted, met with an accident or left home on her own because her parents were about to get divorced. Kenichi takes an exceptional interest in this case as his younger sister Mayuko has been affected emotionally since she was attacked by a man, so he desperately wants to prevent something similar from happening. (Source: Japanese = natalie.mu || Translation = MyDramaList)