The word Sus is meant to suggest that somone is believed to be Shady or false. They are hiding something or are believed to have a serious character flaw which makes them undesirible as a friend or acqaintence. It is derived from its root word Suspect.
Medieval Greek, also known as Byzantine Greek, is the stage of the Greek language between the beginning of the Middle Ages around 600 and the Ottoman conquest of the city of Constantinople in 1453. The latter date marked the end of the Middle Ages in Southeast Europe.
In the classical, or hellenic period, Greek existed in several major dialects, each of which has its own significance for the history of the language, but the most influential of these would ultimately prove to be the one spoken in Athens, called Attic.