Dark chocolate in general has less fat than "milk" chocolate (and also less sugar), but even dark chocolate comes in different percentages--the higher the percentage of cacao, the less fat, and those with 70-85% cacao are considered much better kinds to consume.
And of course, this all assumes you're eating only dark chocolate *without* nuts, fillings, etc...and also that you're eating only a small to *moderate* amount of chocolate!
Re fat:
". . . Cocoa beans contain approximately 50% fat on their own.
The fat is primarily comprised of two saturated fatty acids (palmitic and stearic acids) and one mono-unsaturated acid (oleic acid), in equal portions.**
Cocoa butter and chocolate do not raise blood cholesterol. However, when consuming milk chocolate or lower grade chocolate where a part of the total fat content comes from milk fat or various other types of fat, the cholesterol level might be adversely affected."
Also, the anti-oxidants from flavonoids in dark chocolate (not in milk chocolate) are quite powerful.... can help protect against aging of the body, heart disease, inflammation and inflammatory bowel diseases, effects of stress, are anti-carcinogenic, etc.
Thurada 4EN 051