Barrier
The barrier that separated her love for Battousai, Kenshin, was just thick enough to keep Tomoe's hatred for her fiancé's murderer at bay.
The love for both men, the hatred for the one holding her, it was all a dead end. Her mind was growing hazier by the moment, and she was slowly realizing that Kenshin had finally given her back what he had taken away: Kiyosato.
So she drew a thin line across what Kiyosato had left. As a thread of blood, barely thicker than that barrier between love and hate, began to drip down his cheek, Tomoe died.