
Travelled through time.
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Luca actually travelled back in time. He sincerely wished to have a happier life since both his uncle and aunt died. He ended up all alone . He knows from the past that the FL will work with the people who will hurt him, so he decided to take her with him to the Duke's house so he can keep an eye on her. In his past life he also found out that the ML, his uncle, doesn't love him. The ML died protecting him because he saw it as his responsibilty, but he straight up told Luca that he doesn't love him. Which is why Luca behaves so cold to him in this current life. When the ML thought about either lying to Luca by telling him that he loves Luca or being honest with him, he had decided to be honest by telling him that he doesn't love Luca and then he thought about Luca's aunt, who had abused him, and thought that he and the aunt will be in hell together.
The ML is also not actually blood related to Luca. So Luca thought about his aunt and how he does value having a blood relative with him after all. Luca is confused by how the FL and ML are behaving in the current life , because they were different in his past life. Luca decided to go to the Duke's house so he can expose and punish the person who is plotting against him

She lived in Korea and died. Then reborn as Judith and treated Luca badly because of her love for her deceased sister. But after the death of Judith, Luca learned about her actually saving her life and being involved with Winterwald and the villain in order to protect him. After taking the revenge, Luca had the 2000 years old hidden artifact of Winterwald which belonged to the first emperor, and makes just one wish come true. Luca wished for everybody to have a happy ending. So, the time was reversed back. Because of it, Judith remembered her past life.
PS. Luca who is good at gambling and drinking at 10 years olds' body is the most I want to see in the manhwa
Luca is a regressor and FL is the original aunt.
They never really hated each other.
https://forum.novelupdates.com/threads/i-will-make-an-effort-to-change-the-genre.110458/page-5