Kumoko

The main protagonist of the isekai light novel series So I'm a Spider, so What? is a nameless character who is best known among English-speaking fans by her unofficial nickname Kumoko (literally "spider girl").

That's right, she's a god damned spider. What more could you ask for?

Character profile
Icons

The series' premise is about a nameless female high school student who died, and was reincarnated into an MMORPG-like fantasy world in the form of a "Lesser Taratect", the weakest type of monster that inhabits a massive and dangerous underground labyrinth. The story primarily chronicles the protagonist's evolution from a weak monster to one of the strongest creatures, aided only by her wits and ingenuity.

Kumoko is drawn with a moe-style face to make her stand out from other lesser taratects, and to induce familiarity on the audience.

 Identity (spoilers)  In the Wikipedia's English article on the light novel, the character's name is displayed as Shiraori ( or "White"), which is her given name after she evolves into a creature with the upper half of a beautiful woman and the lower half of a spider. Likewise, the International Saimoe League uses "Shiraori" (consistent among the 4 relevant languages) because it was the first official name used to refer to the character. Despite this, her icon depicts her initial appearance as a spider.

On the other hand, the protagonist is typically entered in r/anime brackets using "Kumoko" since it's the most commonly agreed-upon name among the subreddit's users, and using "Shiraori" would reveal spoilers that will be inevitably pointed out in the contest threads.

Contest profile
In the anime fandom, Kumoko's commonly cited strengths include her personality and the performance of her voice actress Aoi Yuuki.

These traits notwithstanding, the fact that she's a freaking spider has carried her deep in r/anime's Winter 2021 seasonal contest, where she notably defeated Eris Greyrat to become the third #12 seed in seasonal salt history to reach the semi-finals.

Kumoko also qualified for ISML's revamped 2021 winter seasonal league, where she was eliminated in the group stage without scoring a single win.

r/anime brackets
Seasonal Salt - 2021 Winter - seed 12
 * (53) Mirai Shishiou (Dr. Stone S2) 814 - 190
 * (21) Raphael (Tensura S2) 626 - 217
 * (5) Yuki Yoshikawa 694 - 461
 * (4) Eris Greyrat 786 - 610
 * (1) Kyouko Hori 660 - 794

International Saimoe League
'Seasonal League - 2021 Winter'
 * Nomination: 30 votes, 11th
 * Elim. round (30 players, Max 18, Approval): 856 votes, 17th (Prelim 1)
 * Group B: 0W 5L, 6th (Out)
 * Match 1: Miku Nakano 1083 - 2974 (Prelim 2)
 * Match 2: Echidna (Re:Zero) 1305 - 2308 (Prelim 3)
 * Match 3: Setsuna (Redo of Healer) 1141 - 1573 (Prelim 4)
 * Match 4: Roxy Migurdia 978 - 2522 (Prelim 5)
 * Match 5: Renge Miyauchi 1089 - 2271 (Prelim 6)

Honours

 * @Rimuru Tempest Best Isekai Waifu 2021 - Winner