About the Cage of Eden Manga Volume 13

(W/A/CA) Yoshinobu Yamada. Yarai's finally made it inside the mysterious lighthouse by the sea, but like everything on the island, it's more than it seems, full of locked doors. At the top of the tower, a desiccated corpse, crouched in a barrel with a key under its tongue, will give Yarai answers he never bargained for! Meanwhile, Akira and Mariya are still trying to discover the secret to the spire, when two well-dressed ruffians threaten to tear their group apart!