Kagaya had recently sent Shinazugawa and Tomioka on a mission together since, the two pillars never really got along with eachother. So Kagaya didnt have a choice to pair the two pillars on a mission, just to see if they two can get along on the way.

When Shinazugawa had heard his new mission with Tomioka, he cursed to himself that he had to go on a mission with someone he hated for dumb reasons, but he had to suffer through it whether he liked it or not, he had to follow orders anyway.

Shinazegawa was waiting for Tomioka to hurry up before he just goes alone, and do the mission himself “Tomioka, I dont suspect anything from you, just so you know, i want to finish this mission ealry, i dont wanna waste my time on someone like you.”