Arachne silk is one of the items described in Monster Girl Encyclopedia World Guide II. The original arachne profile clarifies that any monster of the arachne species can produce silk. Some arachne subspecies can produce their own, uniquely styled silks: the Ushi-Oni spinning thread similar to a rough, straw rope.
Guide Book EntryEdit
Spider silk produced in the bodies of spider monsters such as Arachne and Jorou-Gumo, and clothing made using it. They're experts at sewing, and using their fine and durable spider silk they can make fine and beautiful clothing. Even among humans it fetches high prices as top quality clothing.
Clothing made with the special material arachne thread using the secret methods of the arachne has several benefits that monsters are glad about. It's durable enough to not tear even when they're going at it like an animal with their husband, and wrinkles are easily undone. Also, when their husband soils the clothing with semen, it can be easily washed off, and although this is so spirit energy glues persistently to it, and continues to remain no matter how many times they wash it. (The odor of semen completely disappears and only the sweet fragrance of spirit energy, which can also be considered the smell of their husband, lingers permanently, but it's only discernible by monsters.)
The more semen ejaculated on the clothing by their husband, the more it carries spirit energy and that fragrance. Just wearing the clothing can envelope them in happiness, as if they're always in their husband's embrace. It makes them really feel like they belong to their husband, and they can assert it to other monsters. In this way, the clothes produced by the arachne are the best suited for wearing while a monster has sex with her husband. For that reason, clothing made by the arachne is especially popular amongst the monsters. Many of the designs are produced with monsters in mind. They incite arousal and passion in men, and they're mainly designed to make them want to have sex with the clothing on. Garments are made with the concept that even if they look wholesome at a glance, they'll still drive men crazy and make them want to sully them.
In this way, most arachne-made clothing is produced with women or monsters in mind. Conversely, clothing for men is hardly ever seen, and almost never circulates in the market. Normally, the arachne almost never make clothes for men. That's because when they do make clothes for men, it has a very significant meaning to them. When an arachne puts clothing made from threads originally meant for binding prey on a man, it means that man is bound to them for life and they'll never let him go no matter what. In other words, to them it's something that only happens once in a lifetime: a proposition of marriage.
They put the strongest love into the clothes they make for their husband, spending the most time and selectively using only the finest thread. The clothes are their finest products. The spider silk used for these clothes is completely glossed with the arachne's overwhelmingly potent love as well as her demonic energy. By wearing these clothes, a man will continue to be perpetually bound by the demonic energy of the arachne. He'll also be showered in demonic energy during intense sex with the arachne, and in no time at all he'll be able to change into an incubus husband just for the arachne.