> Yeah. Tell the boss what's on it, and let her decide whether her cousin
I would just leave to "there seems to be some nasty stuff in there", without going into details - just to show that you've respected the privacy. If she asks what you mean, "well there was some files on the desktop" (or something of the sort).
If she asks you to investigate, then you can pretend to go back into it and come the next day. If not, she may say she doesn't want to know and have you wipe out everything.
In both cases, you have your hands clean. You don't want the guy's lawyer accusing you of planting evidence.
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