All of this stuff is subject to change. I am still working over these ideas.

Gender Differences
There are virtually no differences between males and females. How they tell each other apart is a mystery, but when two meet one another, it is plain to each what the other's gender is. In reality, it is not known how many genders are involved in this race, or how many are needed to reproduce. There may be one, or several. The only hints given are their patterns of speech. "She" and "he" are often said, but they have no written language of their own (that is known) so any variations of these pronouns (such as "shi") are unknown. They instead adopted English from United States scientists and any old written records of their own have been hidden away or destroyed (why is not known).
This race has never been autopsied, and no visible genitalia have been observed.

Physical Variation
They range between very tall to very short, and very thin to very fat. Lifestyle usually does not govern the bulk of these creatures; they remain a consistent size throughout their lives regardless of diet or activity.
They are all the same shade of off-white. When sick, they turn a dull shade of brown; it's believed their blood (or internal fluid) is brown, though why is not known. Their appearance after death is not known.
All individuals have the same sunken, white eyes. The eyes do not glow, per se, but are glassy and seem to hold a very dim light of their own. Why there is a ring of sunken, dead-looking flesh around them is not known.
All individuals have four-digit hands and flat, digit-less feet. The size of the domes of their feet can vary.

Cultural Notes
This race of people is indefinitely strange as compared to modern-day human society. They do not discriminate against one another, there is no sense of competition, and they seem generally incapable of aggression, love, and other passionate emotions. They are typically indifferent and unaffectionate toward one another, and none of them mind this. In their society, they simply strive to keep themselves busy. They work or play constantly until they are tired and decide to eat or sleep.
Currency does not exist between them. They barter only, and usually the deals they make are fair. If one of them has nothing to trade for something he or she needs, that person will work to find something of equal value to trade.
Cars and machinery do not exist. They walk to places they need to be; as a result, they typically gather in very large areas closely together. If one feels the need to move on and live in another area, the distance traveled on foot is immense, but they don't seem to mind.

Diet
These people seem to be omnivorous. They typically eat any plants that they know to be safe, and will occasionally catch and eat small animals. They have never attempted to domesticate livestock, and only farm. They seem to only eat meat when it is an absolute necessity and much prefer a vegetarian diet. As a result, wildlife does not much fear them, and large animals will come by their own will into settlements. Pets do not exist, but animal companions do. Blanks might occasionally take up to talking to a deer or wild goat who will come back and eat the Blank's crops. They never really mind this behavior.