Tonkatsu was something that appeared when Suzu's mother used some sort of ability to get a look at Suzu (nothing on just where she is yet). The only thing known is that Tonkatsu comes from wherever Suzuran currently is. Suzuran just basically left Tonkatsu there to keep Suzu company since she wasn't able to.
A good plan violently executed today is better than a perfect plan executed at some indefinite point in the future. –General George S. Patton, Jr.
Avatar v. 37.0: Fighter Squadron 31. The VF-31 "Tomcatters."