A comparison of the version of the hospital standoff

How the recontextualizes her actions in this episode

: Akise Aru sends a warning to Yuki about Yuno's past, but Yuno "playfully" steals the phone and deletes it before Yuki can read it.

: His "Investigation Diary" loses its power when he is officially labeled a criminal, symbolizing the loss of his identity and authority.

: As they head to see the stars, Yuno carries suspiciously large bags, hinting at the dark secrets (and bodies) she is hiding at her home.

This episode marks a controversial shift in Yuki's character. For the first time, he drops his "whiny" persona—albeit briefly—to actively protect Yuno.

: When Kurusu takes Yuno hostage, Yuki’s diary predicts he will accidentally shoot her if he fires. Defying destiny, he proclaims his love for Yuno and pulls the trigger, managing to hit Kurusu instead.

If you want to dive deeper into why acts the way she does, I can help you break down: The symbolism of the "First World" vs. the "Second World"