The director of Mitsurugi Engine Shin-Yokohama's seventh laboratory branch. Soichiro is currently managing the union's protection and integrity. He is also the one who is giving direct instructions to Mei Amanohokosaka and Es. He seems to try hard to give off a cool and calm impression, but actually has a berserk side of him that he does not like to show. He admires anything cute and seems to have a say in Es' choice of clothing.
Sōichirō appears to be an intelligent man with feminine features. He has bluish sliver jaw-length hair, yellow eyes and wears circular glasses. He wears a modified white coat and a black turtleneck shirt underneath with navy trousers, black boots, and a long bluish sliver scarf that reaches his ankles.
- While not only being a part of Takamagahara he also was the writer of the TOi program under the name TC which is also the name of one of the A.I.s in the Takamagahara-System.
- Sōichirō Unomaru shares some similarities in the personality with Hazama and was also called "Snake" by Sechs. It's recently revealed by Mori in a BlazBlue Radio episode that Terumi's name is not his actual one but another alias he uses and it's implied that Soichiro is Terumi given that they share similiarities.