Quote from juniorg678
I got another theory on this new development. When Haruto went to Tokyo on his school trip, there was scenes of Eba buying a gift for him and being all happy about it. Then she saw Haruto and Kanzaki together. After that, Haruto and Eba didn't meet until that night. Between that time frame, something must've happened to Eba like she was going to be into some kind of accident and Kazama, who said he was trying to get with her for a while, saved her, she found out about his illness and still hurt from the Haruto/Kanzaki incident said yes. It gave her time to write the letter and give it to Haruto that night.
That's an interesting take on it.
I think we need the next half dozen chapters or so focused solely on what happened with Eba between then and now.
All we are seeing is Eba from Haruto's point of view, i.e. an evil manipulative bitch. If we could actually know what's been going on in her world, see what's been going on through her eyes, I might be able to hate her a lot less.