The End of the Maiden's Illusion
Must... Counter... Bittersweetness... With... Pointing out errors...
[spoiler]
CELESTIALS DON'T WORK THAT WAY!
During Scarlet Weather Rhapsody it's mentioned several times that Celestials are those who manage to beat the shinigami that comes to collect their souls, and thus extend their own lifes, but even them are bound to someday lose and finally die.
Also, comic about death and Yuyu doesn't make an appearance? RAGE! Somebody take that kappa to a visit to the netherworld!
Other random related trivia:
-Marisa sucesfully developed an elixir of immortality between Perfect Cherry Blossom and Imperishable Night, but at that time it was too large to swallow, whatever that means. It did mention she kept researching on, which shows that Marisa was interested in immortality. And considering the number of mages in Touhou that become immortal, well, I simply don't see Marisa dying of old age, altough dying on some magic experiment goe wrong isn't too far a stretch. Altough the fact that she somehow returned the books after death sugests that she probably ghostfied Mima-style, but then returned to the afterworld to wait for Reimu.
[/spoiler]