Echoes of Void

From itch.io: Echoes of Void is a mystery adventure where players stumble into an urgent crisis. A building clings to the side of a cliff. The fissure below emits Unreality. Inside, Bellamy, the 7th and Last, has failed to defeat No-Thing who now threatens to unbind the nothingness. Can the players figure out what is happening and stop No-Thing before all is lost?