What is Mon-El's secret?

Since arriving on Earth, Mon-El has been harboring a big secret. He claims that he was a palace guard for the royal family of Daxam and survived his planet's destruction because the noble prince, who he was attempting to save, locking him in the one-man escape ship (a Kryptonian pod) and sent him away.

Who does Mon-El end up with?

Mon-El eventually married Imra and later worked with the worlds' governments to form the Legion, a team of superheroes that followed in Supergirl's image and morals. Seven years later, Mon-El returned to the 21st century with the Legion to help Supergirl battle the Worldkillers before returning to the 31st century.