does r!ciel's soul still exist?
letās organize the facts and sebastianās words:
"and in exchange for this poor sacrifice earned the right to have your heart's desire granted"
"the price you have paid to summon me is your elder brother's soul"
"until the day your silly wish is granted and i can claim your soul"
despite the translator using āyour,ā in the original it is āthat soul,ā which makes more sense considering that ciel is later surprised that sebastian wants his soul. and on top of that, he says it in front of r!cielās body, which suggests to ciel that he is actually referring to his brother's soul.
"i would not be here had the fare for the crossing not been paid"
"and the sacrifice that has been made will never return"
"the fare for crossing has already been well paid"
"i shall claim your soul as my reward"
sebastian does not directly refer to having eaten r!cielās soul. itās possible that his soul was used for the very act of crossing over, as a kind of payment for passage. something like: āa demon cannot materialize in the human world unless a soul is paid as a fee.ā however, this is contradicted by sebastianās words when he says that the willingness to offer your soul is a necessary condition for summoning a demon (and not someone elseās), but some demons come on a whim. so logically, a demon doesnāt need a soul to be sacrificed at all in order to appear.
this leads me to my theory that r!cielās soul was taken as a form of down payment. when sebastian fulfills the conditions of the contract binding him to ciel and returns to hell, he will receive the ādeferred paymentā in the form of r!cielās soul (assuming o!cielās soul has already been consumed).
why did sebastian say that r!cielās soul is irretrievable? he could have meant that the soul is simply waiting for him until he returns to consume it. after all, he neither plans to die nor to give it back to ciel, so it would not be a lie on his part.
so thereās a possibility that if undertaker kills sebastian, heāll recover r!cielās soul ā because there wonāt be anyone to eat it.