Clevatess: Majuu no Ou to Akago to Shikabane no Yuusha

Summary:

Alicia, who had dreamed of becoming a hero since childhood, is chosen by the king as one of the thirteen heroes. Armed with a legendary sword, the heroes set out to defeat the Demon King Clevatess. However, their recklessness triggers a terrible crisis that could wipe out all of humanity on the continent of Edsea. Now, the world's only hope lies with a baby entrusted to the Demon King.