Elder sister has to raise younger sister pure 

writer/painter/original writer
Manastudio / Dandam / Dokyeon
In the world of the romance fantasy novel
Beloved Princess
I found out the truth about my half-sister
Liz, the villainess who brings the world to
devastation.
Which meant, if I raised Liz wrong
The world would be shattered, and I would
die!
I didn’t want to die because I was a coward.
Okay. First, let’s raise my younger sister well