Seeing as Setesh felt no need to know what poison worked best with what course, he figured there was nothing to be found he didn't know already in the bookshelf. The book on Q'Sal seemed quite handy though, especially considering what he had found out about the Alpha Legion's plans involving Q'Sal and the other worldsin the vortex. He needed to go through it more later.
Then there was the mirror. He was unsure how it worked, or what kind of daemon it might contain. Not feeling very fit to do psychic battle in case of possession, he took the mirror without looking at the reflection -- as that's how he assumed it might work -- and stashed it in a compartment on his person, investigating it later instead. He felt an urge to do one last check for anything hidden, before he left, though.
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Awareness test to search for something hidden: (1d100)[10] vs 45
If he doesn't find anything he leaves the quarters to rejoin the others. If he finds something, I guess he takes care of that and then leaves.