I don't have much opinion on the music of the song, but for lyrics it's just messy in organization. Plus a lot of the lyrics seem rude-ish to me, and they don't talk about women in a very classy way. Not to mention some of the lyrics are pretty strong triggers for rape victims.
As for what it's about, it isn't entirely about consent but given the term "blurred lines" is pretty much defined as "It's hard to gauge consent buhh". Tiz a pretty poor song title choice, especially mixed with the spammed "I know you want it" chorus thing.
c: Anywhu just to clear up any possible confusion that could occur over my earliar statement: If someone happens to like the song they're allowed to! I personally don't think well of this song, but anyone else who may like it shan't receive any spite from me or anything.