Yuu Tōsaka, the adopted son of the Tōsaka family, later went to the Clock Tower for "advanced training." His original plan was for him to pursue a career as a magus after graduation... until he stumbled upon a game disc. After opening it, he entered the game's world and encountered Tiamat right at the start. [Quest: Fight alongside Tiamat] "Wait, why aren't you asking me to save Humanity?!" Yuu Tōsaka quickly discovered his blind spot, but he ultimately successfully completed the system quest and spent a wonderful time with Tiamat. ...After that, he journeyed through several different game arcs. In Britain, he was King Arthur's childhood sweetheart. During the Fourth Holy Grail War, he found a girl who adored him... her name was Sajo Aika. After finally completing the game, Yuu Tōsaka was about to put the disc away for safekeeping when, one sunny afternoon, the Heroic Spirits he had captured in the past arrived. The Knight King, Morgan the Fairy, Tiamat, the Root Princess... Looking at the unique Heroic Spirits before him, Tōsaka Yuu began to sweat profusely. "The Heroic Spirit I captured in the game... actually became real?!"

[After the reversal, the killing will be decisive, the content is very rich and exciting, please read it patiently! You will find the treasure!]

A sudden change has filled the originally peaceful world with chaos. The unstable void may tear open a crack at any time, and within the crack is an unknown terror that covets this world.

Two years ago, a naughty little girl wearing a red dress suddenly appeared next to Yun Yi.

The strange thing is that no one else can see her except herself.

As a result, he, who was originally alone, gained a sister.

However, my sister turns into a girl in a red dress with disheveled hair at night.

In this state, she would not respond to herself no matter what she shouted.

Until one time, Yun Yi shouted out of nowhere: "Wife?"

Accidentally involved in the world of ability users, facing terrifying monsters, my wife just moved her slender fingers, and all the monsters were crushed instantly.

"Honey, it seems like you are 100 million points strong?"

Yun Yi looked at everyone helplessly and said, "If I said that my wife did everything just now, would you believe it?"

However, no one but himself could see the girl in red dress standing next to him...

"Why are those contaminations and abilities ineffective on me? Am I immune to the contamination and their abilities?"

Yun Yi looked at his sister and asked.

"Because whether it is taboo objects or psychics, the rules and authority they control are too weak, and of course mortal spirits cannot have an impact on gods."

My sister answered matter-of-factly, as if she was saying something completely normal.