Arachne are the classic spider-type monster girls, renowned for their penchant for tangling men up in their webs and sadistically raping them while immobilized. Despite their fearsome reputation as bondage enthusiasts, arachne are also known for making the finest clothing in the Monster Girl Encyclopedia world out of their silk. Only clothing for women tends to find its way onto the market, though, as the clothes they weave for men count as marriage proposals.
A bug type monster with the lower body of a spider that dwells in dark places such as caves and deep within forests. They have high intelligence, but most of them are lustful and belligerent. Since they have high physical abilities, they are very dangerous creatures.
They make sticky thread inside their body and use it to make a net-like web. these webs function as traps for seizing prey. Animals and people that touch it without realizing, get stuck due to the adhesive power and become unable to move. Of course, they aggressively attack trapped prey and other prey, seeking to wrap it in threads to capture it.
In the case that the prey captured is a human man, they'll attempt a sexual assault for the purpose of procreation. It is said that these sadistic monsters obtain unbearable pleasure and happiness from one-sidedly raping and pleasuring men who can't move, due to the threads when they make them gasp.
Furthermore, the more a man tries to resist and the more rebellious a man is, the stronger it stimulates their sadistic nature. As their desire intensifies, they give the man rougher sex and even more intense pleasure. If caught by them, it's best to just sit there and do nothing without trying to run. That way, there's a higher likelihood of being released.
If a man strikes their fancy, they'll continue to keep him bound in their web and he'll have to keep being with these lustful, indulgent monsters. If a stubborn man decides not to show any reaction after ending up in that situation, then they'll give him an even greater pleasure to make him moan submissively. It's all in vain once a man meekly accepts it because the sex with her will just keep growing infinitely wilder in pursuit of even greater pleasure.
Their main body and threads are weak to fire. For that reason, it's possible to avoid them and their webs to a certain degree if one carries something such as a torch.
Surprisingly, they're proficient in sewing and they sometimes give clothes to men they like. However to them, what it means is "be mine." If one accepts, he'll be bound and he'll have to keep having sex with them as their husband, regardless of consent. The fine and beautiful clothing that they make is even regarded as first-class goods by humans and it fetches a high price due to the danger that accompanies arachnes as well.
Even among the monsters, the demand for their fine clothing is high, as there are designs that incite men's lust and no matter how thick it is, they can still taste pleasure from being fondled over the clothing.
- Although it is unclear if this monster girl or the associate subspecies use venom in their capture of men, there does exist a real world genus of spiders whose venom causes painful erections.