The story begins 3 years after MC has been summoned. Together with his companions, he defeated the demon lord.
He begins planning to build an organization to prevent a demon lord crisis from happening again. He plans to build an Adventurers Guild.
He also wants to start his love life with his female healer companion, but before he can confess his love he was once again summoned…by a demon. The demon is asking for help against adventurers.