When we last saw Kara Danvers / Supergirl (Melissa Benoist), she was just about to give in into her Kryptonian hormonal urges and seal the deal with fellow super-powered alien (Daxamite), Mon-El (Chris Wood). Before they could complete lip-lock, a bizarre, inter dimensional being, Mr. Mxyzptlk (Peter Gadiot), crashed their romantic party, claiming he was Supergirl’s No. 1 Super-fan/Ultimate Fanboy and asking for Supergirl’s hand in matrimony. Perplexed, not to mention flummoxed, Supergirl hemmed and stalled until Mr. Mxyzptlk left the building, but his sudden disappearance didn’t mean he was gone for good; it meant the opposite. Mr. Mxyzptlk was nothing more than a stalker, albeit a stalker with near omnipotence (think of a love-obsessed Q from Star Trek: The Next Generation or the Great Kazoo from The Flintstones).
Love was most definitely in the air around Supergirl’s family and friends too. For Supergirl’s adopted sister, Alex (Chyler Leigh), it was getting her girlfriend, Maggie Sawyer (Floriana Lima), to put aside some not-so-buried trauma from her teen years and celebrate Valentine’s Day like any monogamous, besotted couple. They get there, but only by episode’s end. For the perpetually frustrated, perpetually friend-zoned Winn Schott (Jeremy Jordan), it was meeting a super-cute alien (we know she’s an alien based on the multiple facial appliances covering her face) from a far-off planet, Starhaven. They have a “meet-cute” moment, superhero style too: She beats up a couple of alien thugs who decide to mess with Winn. Their relationship amps up quickly and by the end, they’re all but making a life commitment (or at least a second- or third-date commitment).
For J’onn J’onzz /Martian Manhunter/Hank Henshaw (David Harewood), it’s pining for his semi-love, M’gann M’orzz (Sharon Leal). She’s off on Mars fighting the good fight, joining a burgeoning resistance movement against the super-evil White Martians. He sends her … a letter or a text, a sign apparently of his deep, heartfelt intentions (in the DC universe, Martians can communicate telepathically in case you’re wondering). Sadly, Supergirl’s Season 1 romantic partner, James “Call Me … the Guardian” Olsen (Mehcad Brooks), has been left in the rear-view. He doesn’t even make a token appearance in a romance-themed episode, unsurprising given that Supergirl’s creators decided to move away from a romantic relationship for Supergirl and Olsen, making him all but expendable, at least for the remainder of the second season.
But back to Mr. Mxyzptlk, the fifth dimensional being who just can’t get enough of Supergirl. He also can’t take no for an answer, insistently throwing all manner of romantic gestures Supergirl’s way, everything from flowers and violinists to a familiar monster Mr. Mxyzptlk helps to defeat. He’s an annoyance, an Internet troll sprung to life, but he’s also an annoyance or Internet troll with super-powers. It takes all of Supergirl’s intelligence (or a modest amount of her intelligence if we’re being honest) to figure out a way to permanently defeat Mr. Mxyzptlk and send him back to the fifth dimension where he belongs. It takes a passing comment from Mon-El, though, regarding Mr. Mxyzptlk’s one and only weakness (get him to say his own name in reverse and he’s returned to the fifth dimension), to help Supergirl conjure up a plan to defeat Mr. Mxyzptlk.
Episode 13 might be called, “Mr & Mrs. Mxyzptlk,” but it’s really about the not-quite-on romantic relationship between Supergirl and Mon-El. From everything we’ve learned about Mon-El’s home planet, mid-20th-century sexism and misogyny were the norm, not the exception, and Mon-El was (and is) most definitely a product of a regressive, retrograde culture. He tries repeatedly to White Knight Mr. Mxyzptlk, making things worse in the process. He’s not ready to trust Supergirl even though she’s physically stronger and can fly (among other super-powers). It takes the better part of the episode for Mon-El to admit he’s jealous of Mr. Mxyzptlk, not because he’s almost all-powerful, but because he can give Supergirl the material things she presumably wants and Mon-El, a lowly, lightly employed bartender, can’t.
In the end, Supergirl stands up to both her creepy, near omnipotent stalker, Mr. Mxyzptlk, and her almost boyfriend, Mon-El. To Mr. Mxyzptlk, she lays out the fundamental, underlying principle of Western-style romantic love: It has to be freely given, not bought or coerced. Mr. Mxyzptlk doesn’t quite grasp the message or its meaning moments before he disappears for good, suggesting he might make a return appearance on Supergirl somewhere down the red, blue, and yellow-brick road. Mob-El’s a bit of a hardcase, the unwitting repository of his culture’s backward attitudes and ideas about men, women, and romantic relationships. He claims he’s learned his lesson about romantic boundaries and outdated gender norms, not to mention Earth-style romantic love, but it’s an open question whether he’s really learned it at all or just said he does to mollify a hesitant, doubtful Supergirl and get into her spandex.