Sir Erec, the son of King Lac, is a Knight of the Round Table in the Arthurian legend. He features in numerous Arthurian tales (notably the Post-Vulgate Cycle), but he is most famous as the protagonist in Chrétien de Troyes' first romance, Erec and Enide. Because of Erec and Enide‘s relationship to the Welsh Geraint and Enid, Erec and Geraint are often conflated or confused.
In Chrétien's story, Erec meets his future wife Enide while on a mission to defeat a knight who had mistreated one of Guinevere's servants. The two fall in love and marry, but rumors spread that Erec no longer cares for knighthood or anything else besides his domestic life. Enide cries about these rumors, causing Erec to prove his abilities, both to himself and to his wife, by guising the adventure as a test of Enide's love for him. He has her go on a long, tortuous trip with him where she is forbidden to speak to him. She breaks his conditions several times to warn him of danger, and after a number of adventures that prove both his love and his abilities, husband and wife are reconciled. When Erec's father Lac dies, Erec inherits his kingdom.