Each symbol at the top represents a number. First one one the top right is the corner of the number 1. Accordingly the rest are numbers: 1,6,4,3. Touch them in that order and the door will open.
Eve and her comrades land on the surface to reclaim the extinct Earth and cross paths with a survivor named Adam. Eve is then led by Adam to the last surviving city, Xion, where she meets the elder of the town Orcal and is told many stories. In order to serve her mission to save Earth, Eve develops close relationships…