I dont think it was mentioned before - the existence of fairies I mean, but its not that weird since magic and holy power exist in this world. Phil had a ring filled with holy power and a magic boat was build as well, not to mention that Leguin is the great magician, so its not that really off in this story, makes sense actually. They probably skipped the part mentioning fairies before in the manhwa, but im pretty sure it was said in the novel. I dont think Phil knows the fairy queen, most likely Leguin has some kind of deal with the fairies or is familiar with them since hes someone who lives solely in harmony with magic and doesnt really like humans. I can guess that he has some connection with the fairies and the fairies are aware of him, thats why Leguin went to meet the fairy queen and brought her to Phil after explaining the situation. Since theres no way the fairies will just let it go and ignore Leguin's request (though i doubt he acutally asked her nicely to come) to see the man resposible for killing her kind.
How has she know the fairy queen? Also I don’t remember there being other races at all, is that new?