chairwarmer

\\ˈ ̷ ̷ˌ ̷ ̷ ̷ ̷\ noun

slang : one who habitually lounges in a chair : loafer:

a. : a person (as one not registered as a guest) who sits for prolonged periods in hotel lobbies

b. : an employee (as one in a sedentary occupation) who is superfluous or who makes little effort to apply himself to his work

the seniority rule … discourages ability and efficiency, and encourages the chairwarmer — S.T.Williamson & Herbert Harris