Long ago, Guest was an abandoned child whom no one sought. Garon happened to find him, watched him for a moment, then silently picked him up and brought him to her home. To the other Sins who asked why, she simply said, "I couldn't just leave him." The other Sins, perhaps finding it curious that their demonic abilities didn't work on Guest, took care of him like older sisters.

And so, Guest came to live with the Sins, and a vast amount of time passed.

Now, Guest and the Sins are living together like an ordinary household.

While living peacefully like that...