We Promised to Be Our Old Enemy, but I Have Been Waiting for You for Three Hundred Years.

The Demon Realm is divided into three realms: left, middle and right. Each realm is controlled by a Demon Lord. The Immortal Lord and the Demon Lord in the Middle Realm have been enemies for thousands of years. For thousands of years, the two have had constant disputes. Three hundred years ago, the Immortal Lord went into seclusion because of certain things. When the two met again, it was the place where the Immortal Lord retreated. Intention: Even bitter enemies can be reconciled