"U.N. Owen Was Her?" is the iconic boss theme for Flandre Scarlet from the 2002 bullet hell game Touhou Project 6: The Embodiment of Scarlet Devil. The track achieved legendary status in the mid-2000s through its association with the "Ronald McDonald Insanity" (M.C. Donald) MAD video on Nico Nico Douga, which featured highly edited clips of Ronald McDonald synchronized to the music. The title itself is a play on Agatha Christie’s novel "And Then There Were None," where the character U.N. Owen is a pseudonym for "Unknown." Today, the meme represents the peak of early internet remix culture, often used to accompany chaotic, fast-paced visuals or to signal a "Touhou hijacking" of other media.