all the hashira were being forced to hang out with each other for a week. Master kagaya had assigned rooms in duos of people who he thought should try get along with each other

as everyone knew, sanemi and giyuu hated each other so obviously they got paired. Sanemi despised giyuu, he hated him. He hated his pride and his face and how he acted highly. But, giyuu didn't. He wanted to befriend sanemi and had attempted it but he was never successful when it came to making friends.