Tensei shitara MOB deshita

One day, Grete, the daughter of a viscount realizes that she has been reincarnated as a character of an otome game. But that character is neither the heroine nor the villainess - she is, unexpectedly, a mob character! Moreover, it turns out that if she continues to live according to the scenario, she will be caught up in a fire at the magic school she attends and die without a moment's notice.

As a measure to avoid the death flag, Grete transfers to the Department of Potions and Medicine, which has zero applicants every year, and aims to become a pharmacist!
However, a super-beautiful elite teacher arrives as the new head of the pharmacy department, and she has interactions with the heroine and the villainess... She just wants to survive quietly, but for some reason, she often attracts attention.

The unlucky woman's struggle to survive in another world is about to begin!

(from mangaupdates)