Death's Head Canon, FE4 Gen 2 (V. 1.0)

So.  Being "indisposed" for the better part of two weeks has led to some bizarre trains of thought.  

Not least, I have an idea of the most complete version of FE4 "what happened next" headcanon that I've yet developed.  Unsurprisingly, it's kind of wtf and not entirely based on outcomes or pairings I much like.

Note: In keeping with Fire Emblem and the idea that Gen 2 was followed by a Gen 3, please add 10 years or more to everyone's age if you want real-world approximations for how old characters live to be.  :)

( The gory details... )