The world of Type-Moon starts with saving Altria!

As a master who traveled through time, Ian is not very familiar with Chaldea.But it doesn't matter, he has a special ability that other masters don't have - that is the simulator.This allowed him to leave his mark in history.——Although it’s not quite normal.[You became the husband of the demon concubine, but at the same time you cheated on the Holy Knight King who was disguised as a man. Britain is in a mess because of you. ][You controlled Tamamonomae, and as your master, you let Minamoto no Raikou witness what physical demon exorcism is. The demons of the Heian era all avoided you. ][You made Medusa lose her mind, and all of Greece echoed her words that she would take off her blindfold the moment she met you again.][You are Joan of Arc's soul mate. Only you know how to make this usually extremely reserved saint feel liberated and relaxed in every sense.]Ian had to say that this simulator that understood people's hearts was perfect for him.Solve all problems in his favorite way.Everything looks good.Until the moment they came to him.