I think youre wrong. CLark is not manipulating Alex. He just want to get away with him.
It wasn’t like that at all. If you remember, Clark got really pissed with Alex when he said something along the lines of “I’d kill someone for you if you’d like”.
Alex knew the doc was related to Clark somehow, and confirmed it when he found about the rings. He started realizing that Clark somehow trying to protect the doc and got jealous, so he started “going out” with the doc, to then kill him, since he didn’t want anyone in his way when it came to Clark and his relationship.
So it wasn’t Clark at all, it was Alex’s obsession and jealousy
Clark was manipulating Alex. He said so at the beginning of the relationship. Having sex while friend zoning Alex in order to learn about Alex's reasons for killing. Clark always planned on dropping Alex when he got enough. He just thought he could get away from Alex because, according to Clark, they weren't lovers. Clark should have seen that Alex would get attached.
Clark knew that Alex killed for him once ND he got pissed, but guess what? He didn't do a thing, so he's considered as a part of this crime.
Clark is fascinated with serial killers and he did not plan from the start to stop Alex from killing. And also clark made a dangerous move by making a criminal fall in love with him, it's just natural that this will go back on him and the people around him.
Clark made a dangerous move from the start by playing with a serial killer to fall in love with him and he said from the start that he's manipulating Alex. Clark didn't plan from the start to stop Alex from killing bc he's fascinated with serial killers and didn't report him even though Alex killed for Clark once. It's just natural that this will go back on Clark and the people around him considering Alex's obsession and instability.
Well, I Kinda saw that coming on the way, both Clark and Doc are dealing with a serial killer here and Clark is clearly manipulating Alex to kill more, it happens that this time it's your FRIEND Clark.