Responses
This is in my perspective , I think that the real scene was really kazushi. But the mangaka recreated tht scene by switching the roles to show tht tatsumi dont hv to be alone anymore afraid of using his voice again. Since kazushi will be there listening cus he wanted to.
Like bfore tatsumi was the one comforted kazushi by just sitting beside him but in fact he needed someone to do tht too.

In the beginning it was like this:
http://www.mangago.zone/read-manga/see_you_later_mermaid/uu/ibx_chapter-2/pg-4/
So, why did the roles change here?? They're also a bit older.
http://www.mangago.zone/read-manga/see_you_later_mermaid/uu/ibx_chapter-5/pg-10/
It was the other way around, right? Kazushi was the one crying and Tatsumi was the one who sat beside him.