Mary Sue and Gary Stu characters are like those glittery unicorns in fiction—impossibly perfect, universally adored, and kinda exhausting after a while. They usually lack meaningful flaws, solve every problem effortlessly, and warp the story around their awesomeness. Like, remember that fanfic where the OC ninja saves the 'Naruto' cast single-handedly while Sasuke swoons? Yeah, that vibe. But it's not just skills—it's emotional invincibility too. They never truly struggle, and other characters exist to praise them. Ironically, the term came from a 1973 Star Trek parody, and now it's shorthand for lazy writing. The best characters feel real because they fail, grow, or have messy edges. Sue-types? They're wish-fulfillment mascots, not people.
That said, I don't totally hate the trope. Sometimes overpowered protagonists can be fun—look at Saitama from 'One Punch Man,' whose absurd strength is the joke. But when a story insists we take their perfection seriously? That's when my eyes roll. Even 'Twilight''s Bella, who's technically 'clumsy,' still has every guy obsessed with her. Flaws gotta matter, you know? Otherwise, it's just a PowerPoint presentation on why the author's self-insert is cooler than you.