Red (слэш)

"Each soul is connect by a single red thread that never breaks and would cause extreme heartache to the soul’s whose mates died. The thread wearers were connected to the one soul that they would always belong to, or fit perfectly with. Many swore to never love again after their mate had died and threads slowly disappeared The threads weren’t physical, you couldn’t touch them but they were seen and felt by the heart. When a child is born, and the red thread is clearly visible, it is a time for celebration because the threads mostly develop at a later age. Everyone could see their threads.
Everyone, but Sherlock Holmes."