You know, i often see this detail dismissed, and is such a cool detail so let me self indulge:
First of all, vessel's cloaks are biological, they have it from birth and is inherited from their father (just like their body type)
Second, they are wings, but require monarchwings to be consumed in order to work properly either because void fucked them up or they are vestigial (and therefore would always have been disfunctional)
Third and last, the monarchwings don't *transform* the cloak, just hold the strands together and gives more propelling area (the lighter almost white color is because of the monarchwings own bioluminescence)
Outlined in red, you can see the cloak (biological wings) and in green the actual monarchwings, just as described in the inventory (ethereal, flashing)
