"Urusei Yatsura: Always My Darling" is a two-episode OVA that serves as a continuation of the original "Urusei Yatsura" series, focusing on the chaotic and comedic relationship between Ataru Moroboshi and Lum. The story begins with Ataru, a perpetually unlucky and lecherous high school student, who finds himself once again at the center of intergalactic and supernatural mishaps. Lum, the alien princess from the planet Oniboshi, remains deeply in love with Ataru despite his constant flirtations with other women, creating a dynamic filled with jealousy, misunderstandings, and slapstick humor.

The narrative revolves around a mysterious artifact known as the "Darling Stone," which is said to grant eternal love to whoever possesses it. When the stone is accidentally activated, it causes Lum to lose her memories of Ataru, leading her to believe she is engaged to a handsome alien prince named Lupica. Ataru, initially relieved by Lum's absence, soon realizes the depth of his feelings for her and embarks on a chaotic journey to win her back. Along the way, he faces numerous obstacles, including Lum's new fiancé, who is determined to keep her away from Ataru, and the stone's unpredictable magical effects.

The plot is driven by a mix of romantic tension, absurd comedy, and science fiction elements, characteristic of the "Urusei Yatsura" franchise. Supporting characters, such as Shinobu, Ataru's childhood friend, and the mischievous spirit Cherry, add to the chaos, often complicating Ataru's efforts to reunite with Lum. The story culminates in a series of humorous and heartfelt moments as Ataru confronts his own flaws and attempts to prove his love for Lum, despite the odds stacked against him.

The OVA maintains the series' signature blend of over-the-top humor and emotional undertones, exploring themes of love, loyalty, and self-discovery. Ataru's growth as a character is subtly highlighted, as he transitions from his usual selfish behavior to a more genuine expression of affection for Lum. The resolution ties together the comedic and romantic elements, leaving the central relationship between Ataru and Lum intact while setting the stage for further adventures.