召喚勇者、魔王になる~魔王は勇者に倒されるために魔王軍を作ります~, Summoned Hero Rise to Demond Lord, Shoukan Yuusha, Maou Ni Naru ~ Maou Wa Yuusha Ni Taosa Rerutame Ni Maougun Wo Tsukurimasu
The protagonist is transported to another world. Learning that he can return to his original world if he defeats the Demon King, he overcomes many challenges and defeats the Demon King's army. He passes through the magic circle that will transport him to his original world, but something seems strange...!?