Responses
I think it was kind of shown in chapter 4. It started with chapter 3 at the last panel with tachibana talking about "the girl from back then". To chapter 4, in which sumire takes care of him epsiode, but in a certain page there's a flashback that showed how sumire picked up his papers for his meeting interview. I wouldn't say that it was "save" rather it was helped, and ig she kinda sticked to his head.
It says The End, but we never really got to see how Sumire "saved" Tachibana, did we?