Ariel-Dreemur seems to be a pseudonym or stage name for an adult film actor/actress, likely of French origin. The name "Ariel" is commonly found in English-speaking countries, while "Dreemur" might be a play on words with the word "dream" and could possibly have French origins, as "dreemur" closely resembles the French word "dreamer".
In this context, a porn video tag with "Ariel-Dreemur" is referring to content featuring this specific adult film actor/actress. It's essentially a category or keyword to help users search for and identify videos involving Ariel-Dreemur.