The design on Hearst, Sareena and Misty's boss, I think was a combined effort between Abe and Martin. Martin did some sprites of her in the past and Abe expanded on those for a more concrete look. Really came out great.
Abe also designed the look of that pretty lady in the picture on Hearst's desk, taking time out of his busy schedule to do so. Who is she? I'm sure you'll find out eventually. ^^
Also, love Misty's Clefairy shirt. Actually did a Google search for "Clefairy shirt" and that'd what came up. And I get to draw that jacket of hers again too.
Colors on Hearst, the photo aside, are Abe's work as well - all I did was change the hair color a bit, and needed to change the color used to show off the glasses since it didn't look as good in this art style as it does in his. Not everything works out with everything else, I guess.
Do very much like Heart's look, though. This is also the first look we get at Eighth Sin's base, though it is a limited one. We'll seeing more of that in the next chapter but that'll be awhile.