Okay. I've gone over this and over this, looking at it from every angle I could. This is only my analysis, and please pick apart any logical errors I have made. (And I'm not considering myself as scum, but I am sure everyone is aware that I am unconfirmed.)
I think we have to lynch one of the unclaimed. It is possible that FLoC is being left alive (and a confirmed Mason killed) because FLoC has been under heavy suspicion from the start, way back to when hand banana originated the role. The scum may have felt they could push FLoC's lynch convincingly. (Yes, I'm looking at you, Samruc.)
If I assume that both roleclaims are true, something that is possible (regardless of my personal opinions), then the remaining scum must be Samruc and YagamiLight. So in that case, lynching either one hits scum. We go into tomorrow in excellent shape, with Nano's accurate investigation to guide us.
If I assume that FLoC is telling the truth, and Nano is scum, then either Samruc or YagamiLight is scum. Samruc could be Nano's partner, and so could Yagami. I gain no extra knowledge there. If we lynch either of them, then Nano must investigate one of the other two. If he investigates one and finds them innocent, that one is his partner. If he finds them guilty, then the other one is his partner. (Note that my saying this could in fact skew this result, but I think we have enough evidence to determine who is more believable at this point anyway.)
If I assume that FLoC is scum, and Nano is telling the truth, then only Yagami can be scum with FLoC. Samruc's attacks on FLoC were too sustained and date from the earliest stages of the game, back to hand banana. I see no possibility that FLoC and Samruc are scumbuddies. So if Nano does his investigation on one of the two remaining, assuming that the lynched one was town, then he has a fifty-fifty shot of hitting scum. If he declares one innocent, in this scenario, the other one is scum.
If I assume that both are lying, then logically, if we lynch one of the unclaimed, Nanosauromo will investigate one of the other two. He must find one of them guilty, because if he does not, then it is evident to the other that either FLoC or himself must be scum. An innocent on me means (Samruc/Yagami, whichever one is left) is guilty with a partner in FLoC or Nano, or BOTH FLoC and Nano are. The same is true whichever one he clears. Therefore, I think he will make a false guilty claim against one of us (again, my saying this may skew this result) in this case. And then we're back to relying on evidence, but with a smaller field of suspects. This is worst case scenario, of course. I'm not convinced scum would take a chance like both false-claiming. Seems too risky.
Finally, WIFOM, but I don't see scum tunneling on one player like Samruc did on FLoC. It's too obvious, and too likely to attract unwanted attention. Additionally, Samruc could only be scumbuddies with Nano or Yagami, while Yagami could possibly be scumbuddies with any of the remaining three.
So my vote goes to YagamiLight.
unvote; vote YagamiLight
"Oh, you can't help that," said the Cat: "we're all mad here. I'm mad. You're mad."
"How do you know I'm mad?" said Alice.
"You must be," said the Cat, "or you wouldn't have come here."