This was the most boring, under-developed, trope-tastic, CW script that I have ever read. For a story that's allegedly about sisterhood, there are almost no meaningful character interactions. The girls just declare themselves BFF's after a few days. Every character was flat: a hair color and a gimmick. The only character who was given any motivation was the very obvious antagonist: She wants to magically cure cancer, so... she murders girls and steals their magic. The magical system of this world is cheesy and inconsistent - sometimes the girls have to chant in rhyme, sometimes they just snap their fingers - but everyone agrees that no magic can beat cancer, so... every death was pointless. The PoV characters get wise that somebody within the sorority is trying to perform a wicked ritual: Vivi is told not to bring a magic-enhancing amulet into the group, but she does anyway, handing the antagonist exactly the ritual components she needed; and Scarlett went to track down the killer, found her, ran away instead of confronting her, and then fretted that she needed to go back out and stop the other girl after all, giving the murderer plenty of time to kill again. But cherry on top: Sisterhood is its own power, and when a coven works together they can augment and share their powers, without amulets or wicked rituals - a fact the antagonist knew, but... didn't like the whole "no magical exceptions for cancer" thing, so she betrayed her coven instead. None of these incidents needed to happen! The heroes AND the villain are equally dumb, vain, and irredeemable for having wasted my time.

If you need a witchy sorority/secret society book, read Ninth House by Leigh Bardugo.
If you just need campy witchy rituals and dark academia, watch Wednesday or Sabrina.
If you need a rubric for How Not to Write a Book, watch Writer Brandon McNulty on Youtube.
There is literally never a reason to resort to reading The Ravens.