I think it is because when Tomo and Jun become a couple the purpose/main plot of the story will reach its conclusion, and everything before that will look like extra and pointless.
*after (not before)
But the story shouldn't end with their confession. I mean wouldn't it be fun to see how they would evolve as a couple? Would Tomo act all girly for Jun or stay the same? Would Jun blush everytime he holds tomo's hands and accept that she's a girl. How would Tomo react when she's jealous? And other stuff. Confession and being a couple is a whole different thing
I agree! I would love to see it! <3 But the author build up a tension that revolves around this and will culminate with this as the main theme. If the author wish to continue the story after they become a couple it will need another purpose/tension or all the interactions will seem without meaning enough to hold the readers attetion, because it will seem that is not going anywhere. Well... The author could come up with something, but the main plot (the glue that sticks all the interactions togheter and give meaning to it, creating expectation in the reader) is the "tomo-chan is a girl" theme, when Jun admit to himself that she is a girl and confess the theme will end.
Something he could do is when they get together end Tomo-Chan Wa Onnanoko and start up a season 2 type series with a new theme. That is if he isn't tired of the characters by then.
Why is Carol having more progress than Tomo? Will we always have a detour before finally seeing Jun and Tomo together. I'm happy for Carol but what about Jun and Tomo? I need more of them not less