[TRIGGER WARNING: MENTIONS OF BLOOD, ABUSE AND SELF HARM.]
A world where soulmates are bound by blood. Everytime you bleed and your own blood touches your skin, that same area where it touched it but on your soulmate's body gets painted in pitch black.
Because nothing brings people together better than pain does, right?
Imagine you wake up one morning and your whole body is covered in splatters of black. Your soulmate might've gotten in a car crash and died, for all you know.
Imagine you get a grayish spot. Blood vessels that burst under the skin. Your soulmate got... A hickey? Maybe they aren't looking for you as hard as you're looking for them.
Imagine you go as far as trying to reach your soulmate and connect with them by writing on your arm with your blood. But your soulmate never answers.
A) They don't think talking to you is worth their blood.
B) They didn't receive your messege. Your soulmate is an arm amputee.
Imagine you're watching a famous actor's interview live and they cut their finger on a piece of paper. A black spot suddenly appears on that same finger of yours.
Your soulmate is a victim of abuse. Your soulmate gets nose bleeds.
Your soulmate is a dog trainer.
Your soulmate self harms.
Your soulmate picks at the skin around their nails.
Your soulmate is clumsy.
The possibilities are endless.
The rule may be changed to "everytime blood touches your skin". In which case it doesn't have to be your own blood. Being the soulmate of a first responder, a doctor or surgeon has to be the scariest thing. Or the soulmate of a killer. Never knowing if it's their own blood or not...