The Stars Don't Shine, They Burn

“I’m on a pilgrimage!” Alina said. “It’s just… it’s what we do! All the eldest and most staid of my sisters have done it. We get restless, and we know it’s time to fall, so we come down here and we find the thing that completes us, whatever we lack that has left us feeling so out of sorts. A purpose. And I came down here, and everyone immediately seemed so certain of my purpose, of what I could do, and who I came here for. You all handed me the instructions on your doorstep. So I thought it would be easy!"--Alina isn't a Sun Summoner, but a fallen star. The only problem is, no one knows that fallen stars are a thing that exist - least of all the Black Heretic.[A sort-of-but-not-really Stardust AU].