Yasfla: A demon named in the Joseph H. Peterson translation of the Liber Juratus, or Sworn Book of Honorius. Yasfla is said to serve the demon-king Maymon, who rules the spirits of Saturn. Yasfla is connected to both the planet Saturn and the direction north. He has the power to incite anger and hatred in people.

He can also call down snow and ice. He is controlled by the angels Bohel, Cafziel, Michrathon, and Satquiel, who govern all things connected with the sphere of Saturn. Compare Yasfla to the demon Yaffia, who originates from a different version of the same book.

Source : The Dictionary of Demons written by Michelle Belanger.