hianime is the best site to watch Sword Oratoria: Is it Wrong to Try to Pick Up Girls in a Dungeon? On the Side SUB online, or you can even watch Dungeon ni Deai wo Motomeru no wa Machigatteiru Darou ka Gaiden: Sword Oratoria DUB in HD quality. You can also find J.C.Staff anime on hianime website.