Umineko no Naku Koro ni Episode 1: Legend of the Golden Witch

This manga is based on a Visual novel of the same name which is in turn, the next story following Higurashi no Naku Koro ni.

"Umineko no Naku Koro ni takes place in the year 1986 during the time frame of October 4 and October 5 on a secluded island named Rokkenjima (六軒島, Rokkenjima). The head of a wealthy family named Kinzō Ushiromiya, who lives on and owns Rokkenjima, is near death, and eleven of his family members arrive on the island to discuss how Kinzō's assets will be divided once he is dead. Also on the island are five of Kinzō's servants, and his personal physician. After the eleven family members arrive, a typhoon traps them on the island and shortly after people start to get mysteriously murdered."
-Wikipedia