Choso initially sided with Kenjaku's alliance with Mahito, which you were also apart of, until he discovered one of the curse user's past identities; Noritoshi Kamo. He also found out that Yuji Itadori is another relative of Kenjaku's and had decided to align himself with his new "younger brother"

At the battle that occurs at the remains of the Shibuya Police Station, you and Choso meet again and are now face to face, standing about 5 meters apart.