Rerené Descartes (ルルネ・デカルト, Rurune Dekaruto) is a sorcerer known for the creation of Calculation Spells.
Rerené Descartes is a nod to the great 17th century thinker René Descartes, a first-rate mathematician and philosopher who made lasting and influential contributions to both fields. Descartes provided a modern formulation of the concept of mind-body dualism (the idea that the "mind" or "soul" is non-corporeal and as such does not follow the same physical laws as the body) and attributed many of his most penetrating insights to visions he experienced while either dreaming or resting in a dream-like state.
Magic (魔法, Mahō): A sorcerer, Rerené has the innate capable of manipulating magic at will.
Calculation Spells (演算魔法, Enzan Mahō): Being the creator of this magic, he is proficient in performing calculation spells.
Mathematics: Due to being the creator of his specific magic and it's requirements, he is at least very capable in mathematics.
A capable sorcerer, Rerené at some point in his life created the foundation of the magic type known as "Calculation Spells". The knowledge would pass down to other witches within the Witch Order.