Shuuenchi

It's been a long time since they'd gone out as a family, so Kenji Koyama has taken his wife and kids on a surprise trip. But soon, they get lost, finding themselves at a mysterious amusement park called Happy Land where all the rides are free so that customers can have happiness with "zero lies". But soon, the Koyama family and other park visitors discover the gruesome truth about Happy Land...