Vol. 3 Ch. 5: Overconsumption

After being taken in by Marquis Haiorne's household and constantly having the difference between himself and his younger adoptive sister flaunted before him, Cyril began studying magic to acquire a weapon of his own.

With an aptitude for magic, he could gain an advantage even in noble society.

His younger adoptive sister had no talent for magic, but Cyril did. Born with more magic power than average, he studied magic with single-minded desperation... and eventually developed a disease.

──Magic Power Overconsumption Syndrome.

Humans possess a vessel for storing magic power, but cannot generate magic power inside their bodies. They recover by gradually absorbing small amounts of magic power from outside their bodies.

At that point, the human body cannot store more magic power than the vessel can hold. Once the vessel is full, the body rejects any more magic power and stops absorbing it.

Even after the vessel is full, the body continues to judge itself deficient in magic power and absorbs it on its own──that is Magic Power Overconsumption Syndrome.

It might be similar to binge-eating disorder. Just as a malfunctioning satiety center makes someone crave food, Cyril's body failed to recognize that it was full of magic power and kept absorbing more and more. The excess magic power then corroded the human body and caused magic power poisoning. That was why he needed to regularly release the excess magic power that would not fit in his vessel.

According to his doctor, the disease had apparently been caused by repeatedly putting himself through reckless training.

When he developed the disease, Cyril fell into despair. He was certain the House of Marquis Haiorne would cast him aside...