WiDoW, also known as white diawirline or WDW, is a Class A narcotic that is known for its distinctive black color that can stain the veins and create web-like patterns in the skin of intensive users. When injected intravenously, it causes immediate pain relief, greatly lessens anxiety, and triggers a feeling of euphoria. However, repeated use can lead to collapsed veins, liver and kidney disease, heart conditions, and myriad other health issues.

In SEY 2861, the discovery of the Oso system brought government survey teams to Oso II. Before the detection of the Osoians made travel to Oso II forbidden under the Fair Chance Act, the teams collected a handful of unique native plant samples. One of these, named "nightspiral" for the multicolored swirls on its flowers, struggled to adapt to conditions outside of Oso II. Scientists crossbred the plant using grafting and genetic modification until they created a stable hybrid that produced seeds containing alkaloids. They conducted investigations into the seeds' potential medical applications and intoxicating effects, but their reports were classified.

It is unclear how the seeds made their way out of the lab, but in 2867 a new injectable drug called NightNight appeared on the market. Derived from the nightspiral seeds, it produced a calming and euphoric effect and was sold under the promise that it was not addictive. Demand skyrocketed, but the prohibitive cost of NightNight's manufacture due to the challenges associated with rearing the nightspiral plant kept supply low. Evidence collected by the Advocacy suggests that underground chemists began to iterate on the drug's recipe, eventually reaching a low-cost, purely synthetic version in 2879.

This new formula, sold under the ironic name "white diawirline" or "WDW," rapidly spread throughout the United Empire of Earth (UEE). Users who sought NightNight were offered WDW instead, or were sometimes sold WDW being passed off as genuine NightNight. This tactic hooked more users than might have otherwise fallen under the drug's thrall and guaranteed continual sales for the dealer.

In 2880, WDW made headlines when socialite Khali O'Brien went through sudden, extreme weight loss and black veins appeared on her neck. Friends of O'Brien leaked stories to the press about her plight, and paparazzi began to incessantly tail her. After layers of concealer failed to hide the web-like patterns on her neck and O'Brien took to wearing black turtlenecks and scarves, one gossip columnist nicknamed her the "Black Widow." The name soon stuck to the drug itself, and government officials formally classified it as WiDoW.

The UEE has declared WiDoW use as "one of the most significant public health issues of the 30th century." Billions of UEC have been poured into information campaigns, rehab facilities, addiction counseling, and more, but overall fatality rates among its users have not dropped. The Advocacy runs frequent crackdowns on known makers of WiDoW and offers rewards for bringing dealers to justice. They also arrest users, which credentialed substance abuse counselors and social workers say only makes the lives of these users worse and often ensures that they will not seek help. Activists argue that legalization is the only way to mitigate the harm of the drug, help users who want to become sober, and stop the profitable blackmarket trade. Few politicians support this stance.