Luka is one of the more minor roles of the show however, he is seen in many of the Miraculous Ladybug comics. He will have a good amount of lines, however not as much as Adrien Agreste. 

There is not too much to be said about him. Luka is an average teenage boy with a loving family. He is sweet to the people he cares about. He is a guitarist that sees people's hearts with music. He is the older brother of one of Marinette's friends, Juleka. He has an obvious crush on Marinette and makes it known to her that he likes her. He is very supportive of her and respects her wishes if she decides to go with Adrien instead. He is often seen mature, charming, and very smooth with words.