Isekai Maou to Shoukan Shoujo no Dorei Majutsu - Volume 6 Chapter 3 part4

Ian Percus, the second son of a countryside Viscountcy.

One day, he received a love letter from the future.

‘If we don’t protect the future, the world will perish.’

With an ominous warning scribbled by someone

For Marco, Lucas is his meek little brother. For the rest of the world, he is the menacing Ghost of Vermil.“Angels endow blessings. Demons sow curses.” A hundred years ago, angels and demons descended on earth. It is said they are still here.Annointed with potent holy power, Marco is set to join the Kingdom's Holy Army to fight off the demonic legion. But before that, he must confront the trail of blood and ash that points to Lucas's involvement with the dark side.As mysteries unfold and loyalties fracture, Marco is faced with the question: where does holiness end and damnation begin? If all lines are blurred and the fate of humanity is at stake, will he have enough resolve to strike down the brother he once swore to protect?

System: You are the only human who meets the binding requirements of this system, please bind with me!