Lukanette The Demons Sister

Marinette Al Ghoul Wayne is the older sister to Damien and has been trained from birth to be the best assassin and sister to the heir of the Demons Head, so she was always kind and loving towards her younger brother. After being separated and almost dying, Marinette is found by a lovely couple by the names of Tom Dupain and Sabine Cheng, who take her in as their daughter and nurse her back to health.

After a few years, Marinette dupain-cheng is given the Miraculous of the Ladybug and becomes one of Paris' heroes alongside her partner Cat Noir and eventually a team of other Miraculous users. At age 15, Marinette is made the Guardian of the Miraculous and starts to stress herself out to the point of almost having a breakdown if it wasn't for her very good friend Luka Coufane calming her down and eventually they start to date each other.

Damien Wayne, the youngest son of Bruce Wayne, is lost without his sister and has painted her portrait multiple times from when he last saw her many years ago. His siblings and father have no idea that Damien had a sister they have seen his paintings of a very pretty girl and assume that she is someone Damien has taken an interest in so they have been trying to find information on her.