All models should have a focused or highly suggestive allure or appeal to the viewer. Though eye contact is not mandatory, a coy turn of the head or sultry look will add to the appeal. Generally speaking and specific to this group, fight scenes, distraught or despairing expressions or looks of great hostility and violence are typically not alluring and will detract from an image being added to this group.
A little more information can be found in our group rules (on our main page), as well as our gallery definitions (links are also on our main page).
Happy rendering gang!