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No, unlike Rin, Amaimon is a true demon and his body and powers lie in Gehenna. However, he is able to possess certain objects or humans to surface in Assiah, as he did. Rin merely destroyed the container Amaimon was possessing.Officially he has died in the anime, however (speculation) it may be that his physical body was destroyed and his spirit has returned to Gehenna and he is now in a state of recovery