I'm running the Rise of the Runelords adventure path, and am coming to the end of the first chapter, so prepping to head into the Skinsaw Murders. My concern is this- my players took a real shine to Aldern- including the target of his obsession. I take partial blame for that, since I like to assign photos to NPCs to make them more memorable and I made the mistake of using Kit Harrington for Aldern. And his "Lust" target is now *into* him, despite him being overly familiar early on. She encouraged his crush on her and sought opportunities to hang out with him far beyond what the module suggested, and gave him a keepsake to remind him of her when he left.
So on the one hand, this is great- the players are super-involved and that will make him turning out to be the Skinsaw Man all the more horrifying for them. However, I strongly foresee them figuring out it's him almost immediately- even as the current adventure wraps up they're talking about going to Magnimar to hang out with him, so as soon as the name "Foxglove" comes up in any context (Manor, River, etc.), or most likely as soon as his obsession target gets the very first note addressed to her specifically, they're going to be on it like white on rice.
Anyone have any thoughts on how to handle the mystery such that it will actually be something resembling a mystery? I was toying with the idea of the Skinsaw Man actually being Aldern's brother, and making Aldern simply end up as one of his victims (with the obsession transferring out of Envy more than Lust). I just feel like the blindingly obvious culprit for this group is going to be Aldern, and would rather it not be a case where the party rejects it as too obvious and then has it turn out to be the case anyway.