anyway, read some spoilers if anyone curious:
yeah her soul transfered to a stranger's body in her previous life after she was executed. she has to complete some tasks to return, and while at it, she becomes aidan's personal maid (bc he suffers symptoms of losing his 'pair', but she can alleviate it) and learns that aidan never intended for her to die. she also meets poppy who is suffering the same thing as aidan. her current life body is unconscious but continues to grow but since the time flows differently between the timelines 9 years pass before she returns to her current life. anyway, they defeat the emperor, there is a hidden villain who is also a reincarnator like mc, but mc summons her mom and defeats him. the ml is aidan, poppy is relegated to family. they live happily ever after.
so what's the point of her reincarnating as her sister?