I’m not sure I understand your question, but the “dark” in dark matter is relative. That is, the matter is dark because it cannot be seen against the cosmic background. However, all normal matter radiates until it is at or below the local ambient temperature. Weakly interacting matter does not interact electromagnetically and thus can’t be seen or even “felt” (i.e. is is not subject to the electrostatic repulsion that allows us to interact with normal matter) except by the influence of mass and the nuclear weak force. As far as I am aware, there are really no good models for a WIMP that play nicely with the current Standard Model, so this hypothesis really is speculative at this point.
There’s Dark Flow - clusters of galaxies should be moving randomly in all directions but they seem to be flowing towards one particular region of space