Every palace had wells, and drawing water and delivering it as needed were an important part of a tomusuri's duty. For this reason,
musuri were also called
susa (水賜, literally "giving water") or
susai (水賜伊, a female in charge of giving water) and their residence was called a
susagan (水賜間, a place for those drawing water). On the other hand, male slaves were called
paji (巴只). Although the terms,
susai and
paji do not appear in
Goryeosa, a book compiled about the "History of Goryeo", the
Annals of King Taejong (Taejong sillok) mention the class. From this record the Joseon royal court followed the system of the former state; Goryeo, young boys designated as male slaves were called
paji, in charge of cleaning in the court, while female slaves were called
susai. The record indicates that the system of
susai and
paji existed since the Goryeo Dynasty. The term
musuri was originally used in the
Mongol court, so it is assumed that the term came into use in the late Goryeo period. At first
musuri travelled in and out of the court, but
King Taejong changed the system to prevent their spreading court affairs. Since December 1411 in the
lunar calendar, the musuri stayed at court all the time. ==Roles and class==