[BL] Due to a rare condition, Vince’s end of the red string of fate is tied around his neck, while his soulmate's, Jack, is tied around his finger, like it’s supposed to be.

Theory says that if they "sleep" with someone that isn’t their soulmate, the string tightens on the other end, letting your soulmate know exactly what you are doing.
When Jack feels his string tightening, he feels heartbroken, and starts to sleep around with everybody as revenge, not knowing Vince was a victim of abuse.

When they finally meet, Vince is already suffocating.

or -
Love and fate's hopes for humanity were way too high and all they got was disappointment

Singularity: The Red String Around Your Neck

Jack runs until he can't feel his feet anymore. He runs until his lungs start burning - cause that's what he wants. He wants to feel exactly what he put Vince through all this time. He wants to stop breathing. 


He was so sure that he knew what he was doing. So sure that he had the right to revenge his broken heart by being a terrible person. It's a choice he made. A choice he regretted the time he was done with whoever he chose to sleep with, but he still felt like it was the right one. 


He didn't want to be hurt, but he only ended up hurting himself even more. Even worse - he hurt Vince. He promised to himself he would never hurt the other. 


And now he knows he's the person who did it the most. 


He hates the red string around his finger that now he suddenly seems to be so aware of. 


Chapter XVIII