Loki
About
It is revealed later that Loki is Nakaba's older brother. He also possesses the arcana of time and has been using it from the beginning of the story.
Later in the series, Loki demands that Nakaba gives him Senan. Neither Caesar or Nakaba are willing to fight him, so Loki gets his wishes. Nakaba stays in Belquat to rule with Caesar. All the subpersons in Belquat are relocated to Senan, and all the humans in Senan are relocated in Belquat. The subpersons are officially freed from slavery. Nakaba receives a message from Senan that Loki is dead. She also received a note, but passes out before she can read it. In her arcana, all the locked doors are open, and she learns that Loki is actually her older brother. Their mother told Loki to pretend he was Nakaba's servant outside their village because they'd be killed if the fact that they're siblings is discovered. When Nakaba wakes up, she reads the message from Senan. It's a note from Loki saying that he gives Senan to her. When Rito delivers the news of Loki's death, he tells her Loki's cause of death is from the overuse of his arcana.