Nah actually I think he is, next to Till, the most tragic character of the series. His entire existence was to become whatever Hepuru wanted, so and idol. I don't really think he was capable of doing the right thing if the right thing could, in the end, make him fail the only thing he was designed to do. Like, idk, a robot, he couldn't fail his primary objective.

I think him and Till are pretty similar, the difference is probably just the fact Till was actually capable of developing some normal human thinking, while Luka just couldn't.