Kokuto:
Dammit. Now I'm remembering one of the passages you posted. When XY got assassinated, she was about to die, and sudden she felt a huge surge of [spirit] power surge through to keep her heart beating, and she felt how tormented that power was. SOB
I interpreted the heartbeat in that scene to be XL's (which she felt through the connection while he was still travelling to her), and the devastated spiritual power to be from TSJ.
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She could vividly sense her heart slowly weakening, but just as it was about to stop, she heard another heart beating. It was strong and powerful, leading her heart so that it wouldn’t completely stop. It was like a sole flame in the palms of the hand, seemingly about to be extinguished at any moment, but still flickering weakly with life.
Xiao Yao felt that she heard Xiang Liu snarking at her: Just this and you’re going to give up?
Xiao Yao retorted back at him: What do you mean just this? If you’ve been poked so many holes in like a sieve, air passing through both top and bottom, even if I don’t want to give up I have to give up.
She really had no strength left, so that even the weak sole flame that was keeping her heart beating was too much to sustain. Even with another heart guiding her heart, still the heartbeat grew weaker.
Suddenly power coursed through her, unending streams of power that allowed the weak heartbeat to continue beating.
She couldn’t hear it, couldn’t see it, couldn’t even feel it, but she felt sad because the spiritual power was so sad and devastated. Even the power was crying and Xiao Yao couldn’t even imagine how heartbroken the owner of the spiritual power was.
Xiao Yao wanted to see who was so sad but didn’t have the strength. She could only follow the guidance of the other heart and slowly locked herself up. Just like a flower blooming, the reverse process was to return to being a bud, into a seed, back into the soil, laying in the Winter to wait for the Spring to arrive.