I Took Her In, She Locked Me Out (To Die)

Summary

After working for five years, I finally get to purchase my favorite penthouse in Rainville.

Tessa Boston, my younger cousin who has just graduated from high school, tells me she wants to stay with me during her summer break.

I want to reject her at first, but my mom claims that we're all relatives here, and that I shouldn't act all high and mighty just because I'm richer now.

So, everyone drops Tessa off on my doorstep without even consulting me.

But after Tessa starts living with me, she frequently sings loudly and makes a lot of noise in the middle of the night.