A former researcher for "The Sisters" project. His specialty is creating personality data with self-learning capabilities. During the "Level 6 Shift" project, he was assigned to direct the experiments. Ao hoped the project was a success as he invested a lot of money into it but the project fails due to Tōma and Mikoto's intervention which left him with a large debt.
SpoilerIn desperation, he agrees to join a rival organization outside of Academy City by giving them top secret data and as an act loyalty to his new benefactors, he plants a virus upon Last Order. However he plans are foiled by Accelerator but manages to shoot the esper in the head while the latter was busy saving Last Order. Before he gets the chance to finish Accelerator, he is shot by Kikyō. After a long conversation, Kikyo kills him.
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