I have a theory that bixie may swallow the real sibuxiang,
First,when chapter 400 shows that remains is only few bone and it does not make sense because why it show that it can show skull or something but bone like ribs unless it was digestive,the other chapter show bixie have very good digestive system instantly torn of the thrash bag ,so it make sense because the look how they show sibuxiang bone like being digest because it also left tiny pieces, so it mean the real sibuxiang die in bixie stomach,
second I know some of u may think tanlu kill sibuxiang but remember at chapter 400 show they say that pixiu clan ,why clan Intead pixiu or tanlu the pixiu ? Unless it means they also mean bixie include it , but God knows that why god protects tanlu like what it says in chapter 200,and tanlu say "bixie wake up get sibu" I think he wants to say "get sibuxiang out "it means of bixie stomach,
Is only theory sorry