Admiral, I've got a request. ...You can load me with anything, except those weapons. I'm begging you.

In 1945, in preparation for the final mainland battle, a surface fleet focused on surprise attacks was formed. Kitakami was modified into a Kaiten mother-ship and assigned to said fleet. Among the ships in that fleet who carried Kaiten, Kitakami had the largest displacement and number of launchers. From (Japanese) Wikipedia