When you have a passion for something
Aside from us (of course), it's very sexy to see you love something; to have a deep passion. Whether that passion's for work, a hobby, or a worthy cause, it doesn't matter; being passionate shows a guy that you're a romantic and want something more for yourself. And — especially since a single-income household is a thing of the past — this trait is super hot.
For instance, my girlfriend is passionate about many things, and all of these passions further attract me to her.
For one, she's vegan and her passion for animals is nothing short of inspiring. How she eats a plate of vegetables while I'm mowing down on a gourmet burger across the table I'll never know. Two, she's an incredible baker and bakes whenever she has free time. Because of this, she's managed to turn her art degree into a baking career, where she's head baker at one of the biggest bakeries in our city, just because her employers saw the passion I had seen in her, and rewarded her for it.