Ultima/Chronology

She was recruited by Diablo who was looking for subordinates to help out with chores. At first, Rimuru thought she wasn't strong but Raphael quickly corrected him. She energetically introduced herself and pledged loyalty to Rimuru. She was so cute that Rimuru doubted that she was a daemon at first.

The unnamed Ultima then gained a physical body by fusing together with an Emulated Soul and inhabiting one of the many homunculi bodies prepared by Rimuru. Her skeleton was slightly sculpted to retain her beauty, and gold was mixed in to turn the magisteel into Orichalcum. After she gained the body, Rimuru named her along with her two servants and 200 soldiers. The 2 servants were named Veyron and Zonda. Ultima and Veyron evolved into Daemon Lord while Zonda has his limit as an Arch Daemon released.

She was then assigned to be Chief Prosecutor of the Public Prosecution Office in Tempest. She accepted the job happily and was looking forward to it.