In a previous chapter, an F-rank team also took the drug and it was stated that they were using magic beyond their natural capabilities. However, those were F-Ranks and not everyone in the Resistance is F-Ranked, some like Kanon are A-Ranks so the drug might not have any affect on them. So, they either don't know about the side effect or don't care about the side effect since it may only affect F-Ranks.with a name like Reincarnator for of a drug it doesn't really seem safe, the whole concept around reincarnation is death so...
i'd assume the drug kills the user momentarily to boost them, the issue probably come later since not only would a drug like that be addictive power wise for the powerless i'd also assume constantly stacking reincarnation/death wouldn't exactly be safe.
"I know we may look suspicious. However, we are the one that 'protected' you."
The goddess of... WHAT?!
snort that shit