My name is Erin Avas, daughter of the Marquis. I believed myself to be the only daughter of the esteemed Avas family… until I was seven.

One day, upon learning she had a half-sister who had been raised in secret and subjected to mistreatment, the young Erin took her slender hand and swore:

「I will raise you into a lady befitting my sister!」

As the years passed, her sister, Irene, faced Erin with a stern expression and declared:

「My dear sister… please break off your engagement to Sir Jasper Cattwell.」

Oh?

[Added Note] An e-book adaptation is currently in the works! More details in a few months...!

[Added Note] A continuation of "I Won't Give Up My Strongest, Cutest, and Most Beloved Darlings I Raised."