Not to be THAT person, but.... I hate this song. It's rubbish IMO. I did like most of the music (PoR has the strongest soundtrack of all the DS Castlevanias, if you ask me) but much like the Forgotten Village and An Empty Tome, I found Invitation to be the weakest of the bunch. Give me Dance of Sadness, Jail of Jewels, Victorian Fear, Gears go Awry or Gaze up at the Darkness anyday. Invitation suffers greatly from the actual arrangement IMO. It's disgustingly FUNKY without being very catchy. It is, by far, my least favourite "main protagonist theme" of the entire series.
There, I said it.