That spider there is known as Nephilengys malabarensis, and what’s in that red box is a dick. Notice I said a dick, not his dick. That’s because this is a female. That dick is broken off inside of her as part of the mating ritual of N. malabarensis. You see, these particular spiders go for the praying mantis school of getting busy. When all’s said and done, the female is supposed to turn around and eat the male. The male has evolved a “Get Out of Cannibalism Free” card, however, in the form of its undead dong.
Instead of sticking around for Mrs. N. malabarensis to get her post-coital snack, the male actually detaches his wiener and lets it finish doing its thing on its own (up to seven hours) while he escapes scot-free. Well, maybe not entirely scot-free, because now, like Walter Peck in Ghostbusters, he has no dick.
But it actually works out pretty well for them. The now-eunuch spiders are actually more aggressive and agile than before, which means that one of the most frequently overheard statements in the world of N. malabarensis is probably something like, “Nah, bro, that whole penis thing was just getting in my way anyway.”