Mon-El

Arrowverse

 * 1)  Kara Zor-El / Supergirl  -  After the destruction of his homeworld, Daxom, Mon-el arrives on EArth and and is sheltered by Supergirl and her friends. Although he as at first an immature cur that she can’t stand, he grows up a lot in a year, and the two become a very serious romantic couple. His evil mother then invades the Earth with an army of Daxomites and, to ward them off, Kara is forced to fill the Earth’s atmosphere with small amounts of lead, their weakness. Mon-El is forced to leave the planet.
 * 2)  Imra Ardeen / Saturn Girl  -  He later returns, having traveled to the future and gotten a cure for the lead-weakness. However, for him, it has been seven years. He is only in this time on a mission for the Legion of Superheroes, and is now married to Imra Ardeen. Mon-El explains that his and Imra's marriage was an political one, arranged to bring peace to warring worlds, but that in time they grew to love each other.