Grey’s Anatomy isn’t the only place where doctors build romantic relationships. Though Doctor Harleen Quinzel is most known for her “Mad Love” romance with the Joker, prompting her creation as Harley Quinn in the DC Universe, some may argue her greatest partnership/romance is with another iconic Batman villainess - Doctor Pamela Isley better known as Poison Ivy.
Up until recently, Harley Quinn and Poison Ivy weren’t considered an iconic power couple in the DC Universe, though there’s been non-stop speculation. Over the years the two have been known to share their thoughts and feelings toward each other with some obvious tension and winks to the reader. From their first appearance together in the Batman: The Animated Series episode “Holiday Knights,” kidnapping Bruce Wayne and going on a shopping spree with the billionaire’s uncapped credit cards, the two have clicked. Since then, the friendship has blossomed into romance… according to those who have read every step (and between the lines) along the way.
The two’s romantic relationship wasn’t instant. Poison Ivy has been teased as a Batman love interest many times, and until recently Harley Quinn has been the Joker’s muse to abuse since her inception. But it was Poison Ivy who cautioned Harley against continuing her relationship with the Joker, which continues in the DC Universe Harley Quinn animated series. At the same time, Harley has been the best thing to happen to Ivy, as seen in Batman and Harley Quinn. In this animated movie, Harley has the “manipulative” power to convince Ivy to not destroy the Earth because of their past relationship. Proving, more or less, that her love for Harley is stronger than any other urge.
The friendship turned into a romance during DC’s New 52 relaunch. Prior to the reboot, Harley Quinn and Poison Ivy teamed up on occasion while being close friends and allies. After it, they were shown to be romantically involved (and basing their relationship on mutual respect). One could argue that’s the reason Ivy despises the Joker. But as mentioned above, Ivy eventually helps convince Harley to leave the Joker behind , and in the Gotham City Sirens series, Harley took Ivy to a new level in their relationship that has defined it ever since.
In that series, Harley is the first one to hint that Ivy may be in love with her. She did not expect Ivy to concede her love in the next issue, but the details of her love were never explored… and the series ended before their relationship could be fully addressed. In 2015, fans got the confirmation of the true nature of their relationship, when DC’s official Twitter acknowledged the pair as “Girlfriends without the jealousy of monogamy” (in regards to Jimmy Palmiotti and Amanda Conner’s series).
The referenced series explored their relationship in depth, only to end once Harley asked Ivy to stay for good, but the Siren couldn’t abandon her duties to the environment. Harley was understandably heartbroken and the two went separate ways promising a commitment to each other in the future. That promise was kept in pilot episode of the new animated series Harley Quinn where they reveal a major change in two Harley and Ivy’s relationship. The episode titled, “Til Death Do Us Part”, changes their relationship from a rare occasion to them having strong roots during the time Dr. Harleen Quinzel was Dr. Pamela Isley’s psychiatrist at Arkham Asylum before she was made into the Joker’s Princess of Crime.
Though the episode ended on a positive note, with Harley leaving the Joker’s side to room with Ivy, it is yet to be determined if their relationship will become explicitly romantic once more.