Ah, well I guess this confirms my assumption from the previous page. I'd never given much thought to yu's vomiting aside from it being a basic response to being sickened from distress/poisoning, but considering their memories are tied to their paste, it makes even more sense that they'd vomit when agitated. Vomiting is one way the body tries to expel something detrimental, so if a yukkuri can expel uneasy feelings through their bean paste, then vomiting is a mental, as well as physical, survival mechanism for them. Unless they overdo it and puke out everything...
~Neverending~Seeing their newborn children get eaten in front of their eyes, both yukkuri vomited out their paste (fresh cream).
When both yukkuri woke up after vomiting out the paste that holds their memories, they had already forgotten about the children.
This way, both continued to live as fresh cream serving (child birthing) machines.