the_debt_of_time

regardless of whether either of the involved parties desire it. As this bond is
magically binding, the indebted could commit the act of repayment without
acknowledging it or even against his or her will.
Because the magical binding of a life debt is so resolute and
impossible to resist when called upon, most witches and wizards in such a
debt offer to repay it immediately and without hesitation.
The life debt ritual itself is a spell that calls the debtor to settle
their account by use of Blood Magic and sacrifice. This powerful magic
flows through the pair so strongly that, once enacted, the debtor is bound to
the saviour. Life debts were often abused in times of war, when a Dark
wizard would purposely endanger the life of a witch in order to save her and
indebt her to him. He would then use the life debt ritual to bind the witch
to him against her will, most especially if a proposal of marriage had
already been refused by the witch and her House.
The ritual itself was banned—though never specifically
outlawed—in 1242 after the wizard Cadmus Peverell was thought to have
endangered and subsequently saved the lives of six daughters of a rival
House with the intent to use the life debt ritual to bind them all to him.
Peverell used the leverage over the rival House patriarch in order to gain the
marriage of one daughter willingly as opposed to six by force.
When his betrothed perished before their wedding, it is rumoured
that Cadmus intended to use the life debt ritual to call her from the grave
but was unsuccessful. When performed correctly, the life debt ritual, as
detailed below, can extend through time and space. Though it is powerful
enough to pass beyond the veil, death by Killing Curse is the one exception
to this ritual.
"Exactly what I told him. No one comes back from the Killing Curse." Hermione
shook her head in mild frustration as she recalled her argument with Harry before
Dumbledore's funeral.
With a deep sigh, she closed the book again and reorganised her stacked archive,
but not before placing a red ribbon between the pages. Though unrelated to the Horcrux
search, life debts had always been something of interest to her, and it would not hurt to
keep the page marked for light reading later on.
She had already known a bit about life debts from casual reading, though nothing
about a ritual had been mentioned to her before. She could only imagine the lengths that
greedy wizards would go to in order to hold power over others. Hermione was confident
that she owed a life debt or two to plenty of people. Harry for certain, though he owed her
just as many himself, if not more. She smiled, thinking how grateful she was that this ritual
was, for the most part, unknown. Hermione knew that Severus Snape had owed Harry's
father, James Potter, a life debt for saving him from a werewolf attack during a full moon.