Fergus mac Róich

Fergus mac Róich/Róigh (literally "manliness, son of great stallion") is an Irish hero and a character in the Ulster Cycle of Irish mythology. Formerly the king of Ulster, he is tricked out of the kingship and betrayed by Conchobar mac Nessa, becomes the ally and lover of Conchobar's enemy, queen Medb of Connacht, and joins her expedition against Ulster in the Táin Bó Cúailnge. Fergus is described as being of huge size and sexual potency. This leads him into many a precarious situation as in the story of the Táin Bó Flidhais.