https://www.mangago.me/read-manga/kumo_desu_ga_nani_ka/ (spider fmc, weak to strong)
https://www.mangago.me/read-manga/survive_romance/ (dont let the title trick u, there is no romance and it is such a good horror/psychological read, absolutely life changing)
https://www.mangago.me/read-manga/samurai_in_another_world/ (AMAZING. SO GOOD. LIFE CHANGING. actually such a gem of a story, its so so so good)
i also have a list of more badass fmcs if u want to check it out!!
https://www.mangago.me/home/mangalist/2635480/
can i have a recommendations of stories who has a GIRL BOSS MC without romance