Hatsune Otonashi/Relationships

Yuzuru Otonashi
As Otonashi was the only sibling of Hatsune, it is natural that they were close to each other. Otonashi often visited Hatsune whenever he could and whenever he wasn't busy, but she pestered him to go out and do whatever is that he wanted to do, and to visit her when it was conveniant.

Following Otonashi's revival, it was soon discovered that Hatsune had a bit of luck on her side as her condition improved despite needing a donor. As time continued to pass and various treatments were administered, the constant use of those treatments left her body weak and her condition worsened exponentially. Unknown to her brother, she had signed DNR papers which relinquishes the hospital's ability to revive her in the case her body fails, to which it did.

She had left a parting message for her brother, but it hasn't been released to Otonashi per her wishes until a certain circumstance occurred.

Yuri Nakamura
The initial meeting between Yuri and Hatsune was one of suspicion. Initially, Hatsune was dazed by Yuri's beauty when she entered the room. As she continued on, Hatsune began to think of Yuri as a lunatic or cultist with the way she put her words together and her explanations regarding her knowledge of both her brother, Yuzuru Otonashi, and her own personal conditions.

Hatsune had began to open up once Yuri broke in through the window and brought her to the Battlefront's base as a sign of goodwill to finally bring Otonashi back into the fold. However, she held strong suspicion for the aforementioned reasons of being a cult or just outright crazy. This suspicion was then proved false as Hatsune asked Otonashi what kind of Afterlife he believed in, to which he provided a vague answer that had confirmed everything Yuri had said.

Hatsune held a degree of respect for Yuri, as she began to realize that her condition's deteroriation will eventually lead to her death and it would destroy her brother. Knowing that he will be in good hands, she gave Yuri her permission to kill her so that way she had control over her own death, as well as ensuring that his brother would be taken care of.

In their final meeting, Hatsune asked if Yuri was infatuated with Otonashi, to which she replied no. Then Hatsune asked if she was in love with him, to which it took Yuri a while before denying it. Hatsune called Yuri a liar, and Yuri exited the window.