I'll duplicate to you again what I asked. One positive response and one negative. Ascended Astarion has a positive answer in the first dialogue, "I just wanted you to be happy." There is nothing terrible if there is a similar option in the second dialog.
I read through the entire dialogue tree for this conversation, and where would a second neutral option lead? How could the dialogue tree and later scenes look like?
From a more literature major point of view, the lines "But make no mistake, I will forever remember what you did for me today. And one wicked turn deserves another. So, tell me what you desire. What can I do for my dearest pet?" are probably meant to set up a new frame of mind for Astarion and the player, while mirroring the "This is a gift you know, I won't forget it" from act one. Both are huge moments for his arc, one framed as a gift, another as a transaction.
There are already enough examples in this topic. It could lead to the same variant of the answer "But if you want the gift of immortality, then I can give you this." This option gives out "I want to be a vampire like you." Add a neutral option like "Now I want to deal with the tadpoles" or "You don't have to repay me with something." He may answer a little differently, but at the end add what I said above.
Once again, I'm tired of repeating this, but if Astarion perceives it as a deal that doesn't mean writer can use my character to show this. I can answer Astarion in the first act in a similar way, when he offers sex, that he does not need to pay for "my services". My character doesn't change from the ritual in any way, so why did my answers suddenly change?
