Side Characters that are more well known and popular than the media they come from, even more than the main characters
Scorpion (Mortal Kombat): Even if you aren’t familiar with mortal kombat itself, chances are you know who scorpion is. Even though he doesn’t have that big of a role in most stories in MK he, and to a slightly lesser extent subzero, is still the most popular character of the franchise. More so than Liu Kang, the actual series protagonist.
Bridget (Guilty Gear): Bridget has overtime become far more well known than guilty gear itself, eclipsing every other character in terms of popularity with various merchandise made of her. Fans of Bridget even have a stereotype of never actually playing a guilty gear game and only liking her specifically.
Hatsune Miku (Vocaloid): Miku is very well known cultural icon especially in Japan. Even though some other characters are slowly catching up to her fame, like Kasane Teto, Miku still remains the most well known Vocaloid.
Edit: I’ve been told Miku doesn’t fit this, I made a mistake. Disregard her here