On his way back Perseus ran into something eye catching. As he made his way into the scene he found out that a king was sacrificing his daughter. As a sea monster was about to pull in Andromeda Perseus dove and sliced the monster with his sword and it drowned. He then claimed her as his bride and flew away with her.
When Perseus returned to Sephiros he came to see that he had been tricked and his absence had just given the king time to marry his mother. He saved his mother after showing the head of Medusa.
The whole room got turned into stone figures and Perseus fulfilled the prophecy after his mother showed him that his grandfather was a wedding guest.
The night was then Perseus's wedding. He also went back to thank the gods for helping him by giving them the cap and the shield.
Perseus threw Medusa's head into the sea because it was too much of a threat to keep. To this day it leaves coral as it flows by with the tide.