Fate/Extella Link

The Holy Grail War and its violent aftermath are over. Peace seems to have settled over the virtual world of SE.RA.PH.
Yet a grave new threat lurks in the shadows. One day, while the reborn Servant Altera and Master stroll through the capital, a group of Aggressor programs appear for the first time since the end of the conflict. Leaping in to save the day is the gallant Servant Charlemagne, but after the smoke clears from the battle, young Altera is nowhere to be found
With the peaceful existence of SE.RA.PH. threatened by a new foe, Servant Nero Claudius and her Master, along with this dashing new ally, will have to work together to protect all theyve built. The next seven days will change the destiny of all who dwell in this virtual world!