Is there no such thing as mind reading magic? Just read what his ideal concept of a little sister is, and then hypnotise him and everyone around him into thinking that he had a little sister the whole time.
Funny to see that the Mother is aware of the magic bullshit going around, ratehr than her conveniently forgetting like in most other stories. She's in quite an interesting middle-point between being aware of everything AND being brainwashed.
And looks like the MC is carrying quite the mystery...
That's quite a nice route to take the story, rather than just the MC going this far for a dumb wish without much thought~.
I wonder what's actually going on here.
Wait till it turns out that's actually a childhood friend of his on whom he tried to project his little sister delusions or maybe used her as a model of her ideal little sister.
Oh, now I umderstand, is very easy trigger the TF rat, 2 times im this chapter, bully or says kill and pufff, worst that fb moderation
But why TF rat and not mouse =/, is more fancy petting a mouse what a rat