Positive, open-minded, artistic, creative, friendly, fun-loving, and kink-positive people who like to frolic, make friends, and have fun.
As for romance...
He enjoys the type of woman who - if she and he clicked - would shove him against a wall without warning, send the buttons of his shirt flying as she rips it open, sink her claws into... uh, you get the point. (She would also appreciate him returning the favor.)
Artistic is good.
Philosophical is good too.
Quirky is very good.
Self-confident, successful, brilliantly smart, adventurous, open-minded, and independant are all big plusses.
If you dye your hair, have interesting tattoos, or have body piercings you and he will get along just fine.
No? That's ok too - just remember the tearing of the shirt thing mentioned earlier.