kumoko (kumo desu ga nani ka?)
Alternate names: No-Name, Shiraori (白織), Shiro-chan (白ちゃん)
Kumoko (蜘蛛子) is a fan-made nickname for the main character of Kumo desu ga, Nani ka?, who had remained canonically nameless for a long time.
She used to be a quiet and lonely Japanese high school girl, before a battle in another world between a great Hero and a Demon King spilled over into Kumoko's classroom and caused an explosion that killed everyone inside it. She reincarnated in the form of a spider within a monster-filled labyrinth and with gaps and inaccuracies in her memories of her original life, including her own name, and finds herself having to do everything she can just to survive.
It's later revealed that she was merely a regular spider that inhabited the classroom, and after dying in the magical explosion, she was given by the god "D" some of the memories of one of the students in the class (Wakaba Hiiro, who is also "D"'s human avatar on Earth) in the process of her reincarnation.
She eventually evolves into an arachne, at which point she is finally given a true name of her own by "D", becoming known as "Shiraori".