Equivalent exchange is the principle of this organization. If you want to ask people to do things for you, you must pay an equal amount of money. This price can be many, not just money, but also siblings, or even one's own freedom.
Involving multiple timelines, some timelines are severely damaged
A heroine with strange but normal brain circuits × Itachi Uchiha with strange and abnormal brain circuits
or
A certain heroine with strange but normal brain circuits × a certain Teru Hirano who has a broken leg and is still so promiscuous (depending on the timeline)
Some of the settings or plots refer to the following original works or fan works: "Fullmetal Alchemist", "Gem Kingdom", "Puella Magi Madoka Magica", "Tragedy Is Not What You Want", "Blessing of the Heavenly Official", there will be more if I think of it later.