Green Arrow has some pretty cool villains. Cupid is not one of them. Unlike many ridiculous DC villains, she's a more recent invention, being introduced in Green Arrow/Black Canary #15 in 2009 as a former special ops soldier who enrolled in a sort of super-soldier program that gave her super strength, but also made her emotionally unstable in the extreme. After coming to Star City she becomes obsessed with the Green Arrow, even killing off his enemies at an attempt to win his heart. This isn't the first time a villain has been defined by obsession with the hero; Catwoman has had a thing for Batman for years, and both Electro and Venom have almost no drive outside of their obsessions with Spider-Man, but basing a supervillain off of a mythological symbol of love and giving her a thing for the titular hero is a bit much. Instead of making the character an obsessive basket case, they could have made her a sly femme fatale threatening his relationship with Canary while being a formidable opponent in combat, but instead they just created a homicidal basket case who's more laughable than she is intimidating.