I was going to say that it was a shadow, except then I took a closer look at one of Hector's dialogue portraits and there are a couple small lines that suggest blindfold creases so I'll have to agree with the blindfold assessment.
Well, part of the reason why Hector might garner a fair share of dislike is that he treats his subordinates as if they are disposable,
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or maybe how he's kind of a lying bastard. Or just, you know, the whole "btw I'm only in this for the power trip, give me a second to screw with the universe by merging with Seth and turning into the final boss" bit. That might do it.
... I don't know, actually. I don't like Hector for those reasons. He's interesting as a character, sort of, but I don't like him.