Pictured to the left: A drider and her wife in the process of having sex. However, the drider is a virgin, so she doesn't fully know what to do to make her penis come out (hint: it doesn't).
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Driders are typically defined as appearing as human women from the hips upward, possibly the very bottom of their midriff. The transition from the human half to the drider's spider half is more apparent than that of the alraune, though only six legs are visible. Researchers say that this is due to spiders having six legs, the arms of the human half are counted as two out of the eight. The way drider legs are spaced, however, allows them to keep their balance and mobility even without the extra two legs. The overall shape of the drider is reminiscent of a centaur, with their backside perfectly capable of being mounted by other humans, but there are a couple of reasons why this isn't recommended. One is that drider backs, on average, are less sturdy than the horse-based lower body of a centaur. Spider bodies aren't built to support large amounts of weight for long periods of time, so prolonged mounting can lead to back problems and possible arthritis. The second reason is that driders aren't usually very tall, averaging out at about five feet, five inches. The tallest drider in existence reached all the way up to six feet even, but that's still about average compared to a human.
A normal spider is known to have a hard exoskeleton, but driders do not. Driders are known for having softer exoskeletons, perhaps as a result of their human halves being soft skin, but they are just as tough to scale. This has baffled a number of biologists who work on monster girl research, given how this shouldn't even be possible. Driders are also known to be able to adjust the strength of their webs for a variety of purposes. Weaker silk is often use as bedding for their companions, while stronger silk is for more utilitarian purposes such as rope or binding. Of course, a drider can only make so much silk per week before finding herself exhausted, and any attempt to force futher silk can result in tissue damage. One way for a drider to reload on silk early is to break down and "digest" almost any type of textile within her stomach or abdomen, but this usually results in small amounts of silk and barely enough to keep her going for long periods of time on end.
The most common way for a drider to procreate is to impregnate other human females. While this may seem impossible, given how all driders appear to be females, there do exist different 'genders' of driders. So-called "male" driders possess an internal penis deep within their birth canals, requiring them to insert their mates into their vaginas. While this internal penis may seem like just a fleshy nub, these are in fact functional, but retractable in the event that her partner doesn't wish to have to deal with in on her way inside. Drider children are typically born in twin pairs, or one child and then the other, though not all pregnancies are guaranteed to result in drider children.
Due to their appearance and the usual portrayal of spiders in horror, driders have a number of myths surrounding them that even research can't dispel. For one, there exists the myth that the usual drider serial killer is known to kill her marks similar to her smaller counterparts. This is probably the most egregious of the myths, as driders not only lack fangs, but they also lack any sort of poison that they can use. Another myth is that driders with bangs have more than two eyes. This one may actually vary from drider to drider, even if their children end up being humanoid, though it's possible for them to lose the eyes on their forehead so long as their human eyes remain healthy.
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ZergAlts production in the same setting as
Endune.
