Jenkins' mother lived in poverty and gave birth to him while selling wares on the streets of Oxland; She hid her newborn under the market stand she was selling at and later attempted to dispose of Jenkins. A couple of Nouvish guards had witnessed her attempted murder, arresting her and taking Jenkins from her. Later, the Nouvish court ruled on the execution of Jenkins' mother after discovering during her trial that he had been the result of her prostitution. The monarchy decided to send the bastard child to an orphanage in Mlastina, where Jenkins would spend most of his childhood and start experimenting on dead rats and ravens he found at the orphanage as he got older while studying and documenting their anatomy.

Reaching his teenage years, Jenkins was threatened with the possibility of living on the streets, as nobody seemingly sought to adopt him into their home and the orphanage becoming overcrowded. A nobleman by Calvin Heights came in days before Jenkins' planned eviction from the orphanage and took him to NATION's castle, which was on an isle located close to Mlastina's shores. There, Jenkins would run errands for Calvin, such as the execution of prisoners and draining their blood for Calvin's consumption. Occasionally, Jenkins was tasked to proofread Calvin's letters and even hand said letters to a courier in Mlastina.

In the years following Calvin having adopted Jenkins into NATION, he'd moved on from experimenting on animals and instead began to study the bodies of NATION's victims, as well as becoming increasingly more invested in poisons when torturing or executing prisoners. Soon enough, young Jenkins would put his accumulated medical knowledge to use when several NATION members fell ill with the infamous Drey Plague; In the process, Jenkins found the cure for an illness that so far seemed terminal. Jenkins' cure made rounds outside of NATION's castle, and he became highly sought after all over Nouveau. With that, Jenkins would gather a lot of fortune from ill townspeople asking for his medical attention. When the opportunity called for it, he also offered his self-made poisons to those who seek to get rid of their spouses, rivals, or family members.