I Became the Younger Sister of a Regretful Obsessive Male Lead

I’ve transmigrated into the world of the BL webtoon "In The House of Dolls, There’s Another Doll Living There" where I left my one and only spiteful comment. On top of that, I become the adopted younger sister of my favorite character: the obsessive male lead who is later regretful for his actions but still dies along with the duke in the end. So, I was determined. Since I have transmigrated into this world, I can’t stand by and watch my favorite character die. Additionally, I also don’t want to die. That’s why, author, I'll need to change the tags and the ending of this webtoon slightly! From "Obsessive Male lead" to "Considerate Male Lead". From "Sad Ending" to "Happy Ending". (Source: Kakao, translated) *Note: This is a promotional manhwa for the web novel of the same name.*

When Rachel de Erlando opens her eyes, she realizes she has woken up as a character inside some webnovel. After the initial shock abates, she adapts quickly and leads a happy life with her new parents, or at least, until they die from an accident. Not long after, she gets adopted by Duke Leon, her father’s best friend, and is introduced to her adoptive brother, Lucian de Leon. Rachel finally realizes that she woke up in her favorite BL webtoon which she was reading in her past life. She also recalls that Lucian is the traumatized and obsessive male lead who meets a tragic end but not before he gets tormented by Rachel and consequently kills her. In order to save her favorite character and avoid getting killed herself, Rachel is determined to change the narrative of the story! (Source: Tappytoon) *Note: Includes two extra chapters.*