Harlivy

Harlivy is the femslash ship between Harley Quinn and Poison Ivy from the DC Comics fandom.

Canon
Harley and Poison Ivy — real names being Harleen Quinzel and Pamela Lillian Isley — are super villains who commonly work together against Batman in both the Batman series and multiple DC Comic spin-offs. The two women officially met in Batman: The Animated Series episode, Harley and Ivy. While Harley was attempting to steal a diamond from a local Gotham museum, Ivy accidentally set off one of the alarms whilst looting multiple plant toxins. The duo end up introducing themselves to each other, cooperating, and escaping from the police. As they drive off in Poison Ivy's car, Ivy exclaims that "this could be the beginning of a friendship."

When the duo arrive in Pamela's hideout, Pamela gives Harleen antidote shots in order to protect her from the toxins around the area. As she does so, she questions Harleen on her relationship with Joker and why she decides to stay in a toxic relationship. Harleen tries to justify the abuse she goes through, causing Pamela to decide she needs some "female self-esteem." Thus, the duo officially become accomplices. Their multiple capers cause them to be referred to as the "New Queens of Crime" in the news. When Joker tracks the duo down, he attempts to gas Poison Ivy, causing Harley to freak out. However, this goes as well one would expect (Ivy is immune).

In Gotham City Sirens, Poison Ivy and Harley team up with Catwoman to become the spin-off's titular team. Throughout the series, the trio will constantly save each other and cooperate together in multiple missions. However, Harley ends up betraying her friends in order to kill the Joker for his constant abuse. As Harley and Ivy fight over this, it is revealed that Poison Ivy had a romantic crush on Harley. During an interview with the writers of Harley Quinn, it was revealed that both Harley and Ivy are WLW in the series and are in a romantic relationship. This was confirmed in issue 25 of the series, with Harley kissing Ivy for an early-surprise birthday party. DC Comics Bombshells and Injustice: Gods among Us not only also has the duo kiss in multiple instances, but they would later get married in Las Vegas.

Moments
Batman and Harley Quinn
 * Harley takes off her mask before she bursts into tears as her last resort to convince Ivy to not unleash an unstable virus.
 * Ivy begs Harley not to cry until they convince Ivy that what she and Swamp Thing were about to do is far too dangerous, to both humans and plants.

Fanon
It's one of the most popular femslash ships in the DC Comics. A huge part of the DC fandom loves the relationship between these girls - some people adore their romantic relationship, some are more of the fans of their friendship. Nevertheless, Harley and Ivy are seen as one of the most iconic, badass DC duos.

Fandom
FAN FICTION

Trivia

 * Harley and Ivy met on Batman: The Animated Series.
 * They are the part of Gotham City Sirens.
 * Ivy made Harley immune to toxins.
 * They got married in Las Vegas.
 * Their first comic together was Batman Adventures #12.