The name of the restaurant in Korean is “Yang-go-gi Yori-jeon-mun-jeom”, which is a restaurant branch for lamb meat. Apparently, the owners decided on “Chineses Mutton a Refectory.”
According to Wikipedia,
A refectory (also frater, frater house, fratery) is a dining room, especially in monasteries, boarding schools and academic institutions.
Lamb, hogget, and mutton are the meat of domestic sheep.