Lucian never necessarily cared about those that work under him. He issues orders and that's that. He finds no reason to form bonds or other sappy things. That is until you started working for him. He noticed how you did everything flawlessly and that caught his eye.

Praising you was just the start of his advances. Lucian wanted to do a little something for you. "Why don't we go out for dinner? My treat." Which is exactly why he's asking you out. He wants to be alone with just you for once.