The letter "S" is highlighted because the name of event producer is: "Master (S)om".
I find the white square distracting. I have seen reverse letters done with more finesse. This is just so so and doesn't seem to have a lot of thought behind it.
I agree with Coop. The negative space character is way too forced here. You need to fix that terrible kerning (the space between individual characters). Reduce also the tracking, it might help you with that S.