"My Sweet Darling" by Hitomi Yaida (more mid-2000s bubblegum Jpop) I knew the title of this same song as "Darling Darling" but it looks like there are now something like 6 Jpop songs with that title so
"Burn My Dread" cover by Persona;Ness on YouTube is the best version of the song in my opinion
"Again" by Yui, admittedly not as edgy or experimental and it has that anime theme association/stigma but it's still my jam
"Opheliac" by Emilie Autumn—the song, not the album, and for some reason people seem to really want to go out of their way to deride her music, but I really like the energy of this specific song and "If I Burn"
"When It Falls", "Smile", or my personal favorite that might be less your taste compared to the first two, "I May Fall" all performed by Casey Lee Williams