Yōkai Island
(Book)

Vincent is an online English teacher looking for something to distract him from the recent breakup with his girlfriend. When his brother Brent, and Brent's girlfriend Amira, invite him on a boat trip to an isolated island, he agrees to come. Yōkai Island is believed to be haunted, and that's exactly why so many young people want to visit it. Everyone wants to see the ghost of Junko Isaka - a young Japanese woman roaming the island and whistling. The boatman getting Vincent's group across the lake warns that the island is dangerous, and threatens to leave without them if they don't come back before nightfall. What starts off as harmless exploration of an abandoned island turns into a struggle for survival as the group soon realizes that the boatman was right. By then, they no longer have any means of escaping Yōkai Island. Their only hope for survival is waiting until dawn - and hoping the whistling doesn't find them in the meantime.