Yuuki is saddened by the death of Clayman, and Luminus is saddened by the death of Roy. Steeped in sadness, and having lost their friends, they seek their next move against Rimuru, who has grown in power and become a true Demon Lord.
A religion is a belief system with rituals. The missionary kopimistsamfundet is a religious group centered in Sweden who believe that copying and the sharing of information is the best and most beautiful that is. To have your information copied is a token of appreciation, that someone think you have done something good.