The venerable husband continued as his spouse nodded affirmatively."Yes, well 1k blood coins are scarce to obtain, but as you can see, it was a fine payment".
Why didn't he hand you 100 gold instead?
"We asked for a Blood Favor. Nefarious dealers think a fair trade would be a live human for a blood oath amulet, but this is not the case. Lord Bishop values humans for slave labor like other Wizards, so he will only award market gold value for humans. "
"How much blood does it take to create an authentic coin?"
"The soaking and sealing process takes time and about 1 liter of human blood. Humans only have 5-6 liters, so any more could have disastrous results. So if you killed and drained an adult human, you could get, at best, six blood coins."
"Hence the need to create a stable stockpile of blood that can be stored and traded. ""Blood Favors work at the rudimentary level. Instead of performing a service for a merchant using metal value systems, you could sell some of your blood or obtain blood components from other creatures. A trained alchemist could soak and seal the blood for you into a coin form for some silver shards. People can also mine out igneous rock and soak up blood themselves to have them forged and sealed to form coins."
"For those who are citizens of the Infernal Citadels, blood coins are a common currency. They have more value than the metal shards. So one can go to a market with a blood coin and come back with enough Citadel goods for a family for a month."
The man put the blood coin on the table. He shook his head in disbelief. "I can't believe all this. "
The older man shrugged as he retrieved the coin. A hand blocked his advance.
"I can't believe you told me all this. Thanks so much for the lesson. That this coin has more value than I have ever seen in a lifetime. I can't believe you took the time and coin to bring me back to health when all I am going to do is rob you of this precious rock." He gave a glaring look of caution as he stood up with the blood coin in hand. "I'll be leaving now with this, and your reward is that it will be all I will take. I can take a lot more." He winked at the startled wife.
"You sure about that?" the older man warned.
The ruffian laughed, "Old man, you couldn't rip a piece of paper, let alone take this rock from me. Your wife is just happy I am not taking her too."
"I didn't say that was my wife, young man."
The woman's face melted away, and her form enlarged to a foot above him. Her legs melded together into a congealed form of blood. After the blood demon finished off the hapless sod, it dissolved into its abyss. The owner of a blood oath amulet observed his bloodied thumbprint vanish and become blank. He placed a few small rocks around the bloodied man as they soaked up his lifeblood like a sponge. A knock of the door and the head of the home opened the door; he greeted Ben Amin.
"It was as you said, Ben."
"I can pick em. You have enough stones?"
"Six stones should do it. Three for me and three for you. Not bad for a few weeks work. Please take this empty oath and use my stones for a down payment. We will be setting up shop here soon enough." The merchant bowed and set forth for the West.