A professor of bionomics, Totori Hiroshi decided to switch career and sat for the MPD mid-career recruitment examinations. After passing the exams, he was very happy to learn that he had been assigned to Division 1. A year has since passed, but his partner, Yasunaga Teppei, still finds it hard to reconcile the fact that as a rookie, Totori is still much more senior than him in terms of age.