Harry Potter: The Dark Lord's Childhood Friend in Winter

[My sister, come here. We'll be together forever and ever, all the way to the end of the world.]

The Dark Lord × Original Heroine (not a redemption story)

Sivite accidentally transmigrates and becomes the only daughter of the wealthy, beautiful, and carefree Winter family.

Her only family member living with her is a cool, handsome little boy.

Wait, handsome, what did you say your name was? Tom Riddle?!

In the cold winter, two children born in winter cautiously test each other, learn to trust one another, and become family.

As for Tom becoming the Dark Lord one day, Sivite thinks that before transmigrating, she was just a fragile college student who couldn't even get up for her eight a.m. classes. She has no System and no cheat abilities, so all she can do is let things take their course.

In the name of family, I'll always be by your side, Tom.

[This is my first story, so please forgive any parts that don't make sense. Brain storage space available.]