Responses
It's a cool theory, but it would take some serious myth manipulation to make it work. Is Collete actually Demeter's secret daughter left in the care of a mortal? Would she care enough about Hades trying to marry her to cause winter? I like the idea, because then College wouldn't be mortal (maybe thats why she survived the epidemic), but I think it's more likely Persephone has been omited or hasn't shown up yet. At some point I would imagine at least a short arc with a rival... Guess we'll see, but it's definitely a theory to think about.
But im scared! What if persephone appears Σ(っ°Д °;)っ