Ren is an entity born from Aoba's power, Scrap. His role is to maintain the balance between Aoba and the other entity inside him. Because Ren can only influence Aoba indirectly, later on his voice slowly became unable to reach him. Out of worry, Ren decided to separate himself from Aoba and transferred his consciousness to an old Allmate. As a result, Ren was able to physically influence Aoba through the Allmate. Because of the accident in Rhyme, both Aoba and Ren lost their memories. Consequently, Ren forgot everything about the accident and how he was originally a part of Aoba.
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