What does grey slaughter blue mean?

It means Osamu Dazai in a gray coat and なかはら まこと in a blue coat. Osamu Dazai and なかはら まこと are two characters among the literary dragons, and Taizhong is the most popular cp among the literary dragons, that is, the American emperor. Grey Slayer Blue is a fan setting. In this fan, Osamu Dazai wears a gray coat and なかはら まこと wears a blue coat, so the cp in this fan is gray and blue. "Wen Hao Wild Dog" is a hot-blooded adventure cartoon, written by Chaowu Kafka and painted by He Chun 35. Mainly tells the story of Nakajima Atsushi being driven out of the orphanage and starving to death when he met Osamu Dazai who threw himself into the river in Yokohama.