Sing Me to Sleep is a fun time.  You got humans, wiches, fae, and sirens, each with unique abilities.  I liked the idea of the keal (disguise) beads, which kept me guessing who else is hiding besides Saoirse.  I like Saoirse as a character, but was annoyed with her interactions with Hayes.  First she’s rude, then clams she want to be professional with him.  I felt she was reckless and impulsive.  And Hayes is an annoying boundary stepper, who needs to grow up and recognize his privilege.  He definitely don’t need to be King, but whatever.  I would not have minded more information or first had knowledge expressed about the oppression of the humans.  And it took forever, to find out about Rain, the sister.  I am not normally a YA reader, so not sure if that is the reason I have so many hang ups.  But I did enjoy the story.  I just wished it were fleshed out more.  My favorite part was when Hayes asks Saoirse why she trains so hard to be the best and she asks him, should she strive for mediocrity.  Boo ya.  Loved that line.  Overall, a fun story.  Not sure I would pick up the sequel though.