Kumo Desu ga, Nani ka? - Raw Manga 生漫画

女子高生が異世界で蜘蛛に転生！？　最弱キャラで挑む迷宮サバイバル！

女子高生だった「私」が目覚めると…何故か異世界で「蜘蛛」に転生していた！！種族底辺の「蜘蛛」として迷い込んだ先は毒カエル・大蛇・果ては龍までも跋扈する最悪ダンジョン！？　メンタル最強女子が生き抜く迷宮生存戦略！！

In another world, the Hero and the Demon King continued to oppose each other. As their great magic collided, the explosion crossed over worlds and destroyed a classroom full of high school students. The victims who died in that explosion will be reincarnated in that alternate world. Our heroine, who has the lowest standing in the class, was reincarnated into a spider. She nevertheless faces this challenge head-on with great determination, and adapts to it surprisingly quickly.

This is the story of how our protagonist, who was reborn as a weak spider monster, does whatever needed to survive.