He is often confused with Azazel who is also called Râmêêl ('Arrogant towards God' or 'Evening of God') though they aren't the same Angel. He is one of the archangels of the Christian and Islamic traditions, the Hebrew name meaning "Mercy of God."
There are 20 leaders in the Book of Enoch also called 1 Enoch the section that mentions them reads:
У 7. And these are the names of their leaders: Sêmîazâz, their leader, Arâkîba, Râmêêl, Kôkabîêl, Tâmîêl, Râmîêl, Dânêl, Êzêqêêl, Barâqîjâl, Asâêl, Armârôs, Batârêl, Anânêl, Zaqîêl, Samsâpêêl, Satarêl, Tûrêl, Jômjâêl, Sariêl. 8. These are their chiefs of tens." - R. H. Charles translation, The Book of the Watchers, Chapter VI. Ф
These are the leaders of 200 angels in 1 Enoch that are turned into fallen Angels due to their taking wives, mating with human women, and teaching forbidden knowledge.
Remiel is the angel of hope, and he is credited with two tasks: he is responsible for divine visions, and he guides the souls of the faithful into Heaven. He is called Jeremiel or Uriel in various translations of IV Esdras, and is described as "one of the holy angels whom God has set over those who rise" from the dead.
He is said to have been the archangel responsible for the destruction of the armies of Sennacherib, as well as being the bearer of the instructions of the seven archangels.
Ramiel shouldn't be confused with Remiel, which is described as the angel that watches over those that are to resurrect, according to Enoch chapter 20.