You have the ability to absorb the practical expertise of anyone you focus on.
The skills you can absorb can be increased by things such as eye contact or physical contact, with each connection made increasing the breadth and depth of what you are able to steal, whether a specific skill or a target's general skill set.
Unless you completely steal a target's skill, they will regain the skill over time.
You permanently retain any stolen skills and can improve them by re-stealing partially stollen skills or stealing similar skills.