ばか！バカ！　馬鹿ー月！

“That doll’s true appearance is a bird greater than you in size. She once fell in love with a traveling cenobite, and together the two had spent many years working together to build a church. But no matter how many years went by, that doll would never age, and thus the cenobite grew suspicious. Surely you can guess how things developed after that?”

Perhaps he was just imagining things, but Lawrence seemed to feel Horo tighten the grip of her arms.

Lawrence felt that he seemed to understand the reason Deanna collected ancient legends and protected the alchemists.

Well, the Cenobite that was building the churches can be assumed to have been a follower of the Church. Also assumed from this is that Deanara (spelling off) didn't reveal her true identity to him. So year after year as he got older and she didn't, he grew suspicious, and probably thought she was possesed by a demon, and tried to kill her or something....It's that kind of thing.

As for why she collects ancient legends and protects the alchemists....The only thing I can think of is....actually...I'm kind of at a loss on this one as well...haha. Maybe she thought the alchemists were the kind of people that, since they go against the church, are the only people who could ever 'maybe' accept her if they knew her true identity. As for the ancient legends, perhaps it's just to hear stories about dieties and humans that fall and love, and it works out.

In AS board are talking about her managing to create through alchemy the phil stone, so her lover or any human could live eternally

You'll say something about the phil stone changing things into gold, but it seems it can be called elixir of youth or can create it.