He was an originally a child with the ability to speak with animals and materialize people's wishes due to his status as a "planet terminal."

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The inhabitants of his village removed his arms and legs to keep him from ever leaving, all while revering him as a deity for their own convenience. Crimson Moon took note of this, and challenged the villagers to a morbid game: all throughout the night, the villagers would have to imagine beasts for Merem to materialize, and if none of the creatures were able to defeat him by daybreak, they would all be slaughtered. Nothing from their imaginations could possibly stand up to Crimson Moon, so he kept his promise and killed all of them at dawn. The act of materializing the beasts was too much for Merem to bear, which lead to his death. He was revived by Crimson Moon as an Apostle and told, that as he was now free of his captors, to imagine beasts to replace his lost limbs. Merem feels an immense sense of gratitude towards him, which he has directed towards his golden princess, Arcueid, since his destruction.

Merem is acquaintances with Gransurg Blackmore, considering him to be both a friend and an enemy at the same time. They both consider Crimson Moon as their god, but they are at odds with one another, as Merem sees him as an idol whereas Blackmore sees him as a master.

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He has always wished to fight Blackmore for the millennium they have known each other, and he plans to do so while under orders from the Church to stop the Aylesbury Ritual. He hates Altrouge Brunestud, calling her an impostor of Crimson Moon who stole Arcueid's long hair. He would only be able to kill one of her bodyguards while also facing destruction, so he is willing to fight alongside Blackmore in order to kill her.