Agent Sinkonnen was a male Human that was assigned to the President Nanietta Bacco's Protection Detail in the late 24th century.
In 2384, when Captain Jean-Luc Picard requested to speak with Bacco in person, Agents th'Neyloh and Sinkonnen were sent to frisk and make sure Picard didn't have any weapons on him, before meeting the President. Once they determined he was clean, they escorted Picard to Bacco. (TNG - Cold Equations novel: Silent Weapons)