The day Aya discovered anal vore.
It was a long and tiring process the first time Aya and her other selves tried experimenting with anal vore, and it mainly just left Aya with a very sore butt afterwards. Ultimately though she discovered that it was a functional way to recombine should they choose to utilize it in the future. She hoped, though, that after some practice, it might be a slightly less uncomfortable endeavor.