A playful cat-like nyan vocal from Project Sekai character Rui, used in memes and edits for cute, teasing or mischievous moments in fan videos.
Ruida Nyan is a short, singsong vocal clip built around a repeated nyan, delivered in a bright, teasing tone that sounds half cat, half playful taunt. The voice rises and falls like a little melody, stretching the final syllable just long enough to feel cheeky rather than cute alone. It lands instantly because the sound is simple and instantly recognisable, even without any words around it. In a video it creates a sudden shift in mood, turning a normal scene into something silly, flirty or mischievous, and it works best when the character on screen is smirking, hiding something or about to cause trouble.
The clip is associated with the Vocaloid and Project Sekai fan community, where Rui is a well known character, and it circulates mainly as a short shareable vocal rather than a full song. Its appeal comes from how easily the nyan sound travels across edits, memes and short videos, where a few seconds are enough to signal playfulness without needing dialogue. Because it is short, light and instantly readable, creators keep returning to it for character edits, reaction moments and cute or teasing scenes, especially in fan-made Project Sekai content.