At the end of autumn episode from Satoshi's POV, she comes back in full gyaru mode and humilates Satoshi, saying she's pregnant with Kujo's baby. There is 0 chance she ever comes back to her previous life.
And about Saki, the whole spring episode is a parallel to Spring episode. It's about how Satoshi tries to become the bull, but fails. He is successfull at first, Saki is getting corrupted, tattoed and fucked in front of her son's body, but when she notices that Kotaro is hyper ventilating, that's when she comes back to her senses and Satoshi's plan fails. At least, that's my interpretation.