The Devil is a Part-Timer: How Much Has Sadao Changed Since Season 1?

As anime shows progress from season to season, there are often dramatic changes in characters. Sometimes shows shuffle between studios, sometimes actors change, and sometimes a new arc simply brings about major obstacles and growth for a given character. In the case of The Devil is a Part-Timer! a nearly nine-year gap between seasons can likely be the cause of the vast majority of changes that have been seen between the two seasons. However, unlike many of the other characters, Sadao Mao has stayed fairly true to the original vision, although he is perhaps less apologetic about it.

Source: Gamerant