Disclaimer: What the hell do you think?
AN: Su Li is a character who appeared in the early drafts of Harry Potter, but isn't shown in canon, so it is a bit of a push to refer to her as a canon character. Still, she is mentioned enough for me to push it, ever so slightly, into the realm of canon.
AN2: On deviantart, someone mentioned that they saw Su Li as Korean on the basis of her surname and I've just run with it.
Su Li was used to being invisible. Not literally invisible, but the invisibility of being ignored and overlooked by people around her.
Her father was the Magic Attaché to the Korean Embassy and always busy with the British Ministry. Her mother had died when Su was less than a year old and her busy, busy father had no idea how to handle his growing daughter. So he left her to a series of childminders and nannies and the like and told himself that it didn't matter, she was only a half-blood anyway.
At Hogwarts, Su buried herself in her schoolwork. She didn't need friends, that's what she told herself. Friends were a distraction from her schoolwork, distractions that she didn't need. But it didn't stop her feeling a pang of hurt every time she saw the Golden Trio, or the every popular Cho Chang with her giggling friends. Even Luna had Ginny and her imaginary, crazy, creatures.
Except, for all her studying and hard work, it wasn't her that the teachers gushed over, but Hermione Granger. Oh it wasn't that they didn't praise her for doing well, merely that she never stood out.
It was during the Year of Hell that Su Li was truly glad of her invisibility for the only time in her life. The Carrows were vicious thugs and there were students who enjoyed performing the Cruciatus curse far too much. Being a student that nobody noticed meant that nobody paid you any attention. And that made her a damn good spy for the DA. People just talked as though she wasn't there at all.
But Su Li was not invisible to Fenrir Greyback when he ripped out her throat. She wasn't invisible to Harry Potter, who was there at her funeral. And she wasn't invisible to her mother, who held her spirit close in death and provided the parent she never really had in life.
