I Became The Younger Sister Of A Regretful Obsessive Male Lead

Ive transmigrated into the world of the BL webtoon after leaving a single spiteful comment on it
On top of that I became the adopted younger sister of my favorite character the obsessive male lead who later regrets his actions but still dies without ever getting his happy ending
Since I have transmigrated into this world I cant simply stand by and watch my favorite character die
Also I also dont want to die myself
Thats why author Ill need to change the tags and the ending of this webtoon slightly
Brother please smile like that in front of others as well I said to Lucian who doesnt smile even a little bit in front of others
Was that request too out of the blue Lucian looked at me with a peculiar expression
If you do that I will give you a gift I said because I wanted to help him in anyway I could He looked at me for a bit and hesitated before replying A gift Is anything fine
Of course The moment I said that his expression changed right away to that of a starving predator Did I make mistake Then Lucian calmly replied with an expression full of expectation
Give yourself to me Rachel Huh What did he say What did he just ask for