KENKI RENKA: RE:ZERO KARA HAJIMERU ISEKAI SEIKATSU†SHINMEITAN

When a demon falls for an angel... Long ago, a great war raged between the royal military forces of Lugnica and the demi-humans. A hero was born on that battlefield--the Sword Demon, Wilhelm Trias. This is the story of that legendary swordsman--and the woman he loved. Note: Includes 1 extra chapter. — Description from AniList community (anilist.co).