Parallel World Pharmacy's Magic System, Explained

gamerant.com:

Parallel World Pharmacy (or Isekai Yakkyoku) introduces a relatively unique magic system whereby each user has an affinity for a particular element. During a reincarnation mishap (or in this case, a blessing), a 31-year-old world-famous medical researcher works himself to death, only to reawaken as a young Royal Court pharmacist'sapprentice.

Falma de Médiciss (also spelled Farma, for pun's sake) has a second chance at life, this time around with the added benefit (and subsequent consequences) of unimaginable magical attributes, elevating the 10-year-old boy to god-status overnight.

Isekai Ojisan: Losing Momentum with Gusto

Parallel World Pharmacy incorporates Science into the supernatural world in a unique and compelling way (particularly in Falma's case.) In this medieval setting, it seems only those born of Noble blood are bestowed with magical talents, emphasizing the element of exclusivity, which is a long-running theme throughout the storyline. Within a world where demons possess humans and the church has a worrying amount of authority, everyone appears to be trying to make a pretty penny from the pharmaceutical field by selling overpriced medicines, astrology-based healing, or unverified herbal remedies to chronically ill (or simply superstitious) customers.

The political hierarchy of the San Fleuve Empire is greatly influenced by each candidate's Divine Arts, with the Empress supposedly sitting at the highest level (although, ironically, Falma faces possible jail time or worse if his extensive magical attributes are discovered.) To prove one's worth, a holy crest marks the bodies of those blessed by the gods, with Falma's divine mark conveniently forming two Lichtenberg shapes which could be explained away by science,