No?

Well, I suppose you have always been the more adaptive one between you both. [That serene(ly amused) expression sticks within those bridging segues between one topic and the next. The lack of finely-honed awareness only endearing at its core. Sweet Fenris. Sweet pair that holds his lifeless heart within their fractious hands (he did not mean to love them both, but once he fell, there was no choice). Those initial miles of affection that felt like inches, and he knew by the time Fenris had been nursed to health that there would be no escaping it.

It would sting, that first meeting (and it had stung), and here they are still wading through its shadow.]

If I'm being asked to guess?

I imagine it must stem from his old life— but where the line of that is drawn, it's possible even Astarion is unaware why or where it started. After all, death— the loss it forced upon all our shoulders— you know it as well as I do: that is no small burden.

[Astarion has never enjoyed speaking of his past, not even to his sire.]

Have you never discussed your former lives?