okay so wait, in the Vanilla Recluse AU since smilk doesn't know that pure vanilla has the soul jam and that's what's making him immortal how exactly does smilk think pure vanilla is alive after so long? or is pure vanilla just built different in this AU?
also is smilk just not quite as evil in this au as he is in canon? cause I feel like if he was really awful after his corruption pure vanilla would've waited to take him out from the tree till he could've at least lessened the corruption. was he just more chill since he had pure vanilla with him? just evil/corrupted enough for the witches to seal him but not bad enough that pure vanilla thinks he deserved to be sealed
also not sure if you mentioned it or not but how was dark enchantress sealed in the moonstone this time since pure vanilla wouldn't have done it?
He's built different /jk
But really, Vanilla explains it offhandedly as a half truth. He's tied to the Endless Archives, which is true. It keeps him alive, which is also true, since the damage to the souljam he self inflicted effected his health greatly. The Endless Archive's magic makes up for the backlash he gets for rejecting the Souljam of Truth. So, he explains it as the Archive keeping him from dying of old age or sickness, but not preventing him from dying of via being crumbled or something like that. Shadow Milk can likely tell something's being left out of the explanation, but at the time it was given he was still getting his bearings about a new body and reeling a bit over Pure Vanilla still being alive.
Shadow Milk is...complicated. The corruption of his souljam and his fall into deceit isn't as black and white as him being good or evil. At the time of him corrupting it was the right thing to seal him into the tree. It was an overwhelming imbalance in all of the beasts caused not just by themselves but the world around them taking them and their virtues for granted. Blueberry Milk's decent into Shadow Milk was a road paved with good intentions. The burden all the beasts carried was so heavy it broke them. Shadow Milk's last act before giving into to corruption was to get teleport a good chunk of his citizens and students to safety, including Vanilla. It was a brawl between beasts. I will eventually get more into this down the road. I do have a bit of a comic planned to explain the aftermath of things.
Vanilla...is a kind person, but a bit more?? Self serving in this au...a little more selfish. He doesn't have a kingdom. He doesn't have a kingdom's people to put first, though he does put cookies he considers part of his family and his own before himself...and Shadow Milk is one of his own. He loves him and he hates the witches, so he thinks what they did was cruel when the witches obviously have the power to at least purify the souljams of whatever built of negativity they might have absorbed...or at least that's his working theory on why this happened. He also thinks that the souljams are cursed objects, though it is not at simple as that, but the trauma of everything just...did mess with his perspective a bit. But he's sure there must have been a better way.
Vanilla had a sister back in the beast era and she went on to found the Vanilla Kingdom and her decedent takes PV's place in the ancient heroes group, but without a souljam they do indeed die when they seal Dark Enchantress. They stole a book of dark moon magic spells they last time they visited Vanilla in the archives before the fight with Dark Enchantress, and used their own life powder as a conduit. Vanilla is...sad about it, in the detached sort of way some mourns a distant relative they hardly know. He was more upset about Dark Enchantress, considering they were actually good friends and she went against his advice at every turn, and fed into the dark magic in her dough's urge to cause chaos. Hence why he was actually a bit passive aggressive for a bit when they met again after she was freed.