These dialogues are from a 2007 J2ME game Nowhere. They were extracted from a binary file within jar file simply named t.
There were no names, and it only started simply as "@[alphabet]" etc. I have manually replaced that with actual names. I discovered majority of them by searching the names, as many characters introduced themselves through that. For example,
@bI'm Sophia.
This tells us that all occurances of @B are of Sophia.
@a is shared by both Lucas, John, who also share the same sprite hence that is not modified. The modifications I made are as follows: