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Melorae is one of the Nomai who came to the Solar System via the Vessel. She was on board Escape Pod 2 together with Rhus, Bur, Annona and Coleus, which landed on Ember Twin. She suggests & finds the location for the Sunless City. After settling down in the Sunless City she was involved in speculations about the Quantum Moon. She and her student Coleus also studied the Anglerfish aswell as the Quantum Moon Shard on Ember Twin.
In the Old Settlement is a mention of Melorae beeing the Aunt of Thatch.
There is reason to believe that Melorae died before the Ash Twin Project.
There are multiple conversations that can be found with her, including inside the Sunless City and the Quantum Moon Locator.