"Eldar" is a word from the Tolkienverse that refers to a large portion (but very importantly, not all) of the elves living in Middle-earth and Valinor. The critical difference is that the Eldar are elves who accepted the summons of the Valar and came to Valinor – those who did not are called the Avari and have been referred to as "wild" and "less wise" than the Eldar.
There is also a species in Warhammer 40,000 called the Eldar, though aside from the name and somewhat elf-like nature, these Eldar have nothing in common with their Tolkienverse counterparts. Creating a god of hedonism through millennia of nonstop orgies would not happen in Arda.