There Is Only One Place for Resurrection

You wake up on a luxury cruise ship. The people on the boat tell you that this is a three-day and two-night sea trip, and guests who have lost relatives or friends are invited to participate. When the ship leaves the shore, the missed dead will be revived on the ship, just as they were before they were alive. But when the journey ends, only one of the dead can truly return from the underworld. You have lost your memory and know nothing about anything. Are you the deceased or the guest? Who are you here for? Detective, spellcaster, psychic... Solve the puzzle before they do, or you'll fail miserably. *The third person of the text * Mainly covers Umineko and Conan. If you haven't watched Umineko, it's okay. Intention: friendship