Cool? Not really sure what the question here is.
Codominance is when both alleles are expressed - one allele is not more dominant than the other.
An example of this is a cow with red and white hair, you can see both colors of hair, not just one.
A MacGuffin is that object in a film which is critical to the characters, but carries insignificant meaning for the audience.
A MacGuffin, a term introduced and widely used by Alfred Hitchcock is some element which drives the plot. The audience is not very concerned with the specifics of it.
