The Strongest Heroes, Now in Their 40’s, Once Again Become Warriors on the Battlefield

The Seven legendary heroes are overwhelming!
The war of extinction “Titanomachy” ended with humanity completely destroying the demons and winning.
Twenty-five years have passed since then. Alain, one of the seven heroes who subdued the Demon King Beelzebub in the war, is already 43 years old. As a knight captain on the frontier, he was spending peaceful days, sandwiched between inflexible lords and annoying subordinates.
But things change suddenly. The demon army that should have been destroyed suddenly revived and attacked. The subordinates were defeated in vain. The aristocrats just pushed the responsibility on others.
So Alain stood up again. This time, in order to break the sword and connect to the next generation. In response to that, the former comrades gather again.
Seven legends are returning to the battlefield now !!