"Haiyoru! Nyaruani: Remember My Mr. Lovecraft" is a surreal and comedic anime series that blends cosmic horror with slice-of-life elements, inspired by the works of H.P. Lovecraft. The story centers on Nyarlathotep, a chaotic and mischievous Outer God who takes on the form of a human girl and lives in a small Japanese town. Alongside her is her roommate, a human girl named Mahiro Yasaka, who is often dragged into Nyarlathotep's bizarre antics. The series explores their daily lives, which are anything but ordinary, as Nyarlathotep frequently invokes supernatural phenomena, interacts with other eldritch beings, and disrupts the mundane world with her otherworldly powers.

The narrative is episodic, with each episode presenting a self-contained story that often parodies Lovecraftian horror tropes while maintaining a lighthearted tone. Nyarlathotep's unpredictable behavior and her penchant for causing chaos create humorous situations, while Mahiro serves as the grounded, often exasperated counterpart trying to make sense of the madness. Other characters include Cthugha, a fiery and impulsive entity who frequently clashes with Nyarlathotep, and Hastur, a more reserved and enigmatic figure who occasionally appears to complicate matters. The series also features appearances from other Lovecraftian deities and creatures, reimagined in a comedic and often absurd context.

The plot does not follow a linear progression but instead focuses on the interactions between the characters and the strange events that unfold around them. Themes of cosmic insignificance and existential dread, common in Lovecraft's works, are present but are treated with humor and irreverence. The anime balances its comedic elements with moments of surreal and unsettling imagery, creating a unique tone that oscillates between absurdity and unease. Through its quirky characters and unconventional storytelling, "Haiyoru! Nyaruani: Remember My Mr. Lovecraft" offers a distinctive take on the Lovecraftian mythos, blending horror and comedy in a way that is both entertaining and unconventional.