Here's an excerpt from the translated transcript of the radio show
All right Koharusbiggestfanever, BloomingKoubou, Lawrence; defend koha's insinuating sayu's dream of being a MMusu is a lie as 'nothing wrong about it' (though I'd advise against doing so in Sayu's thread )Sayumi: I'm completely satisfied just being in Morning Musume.
Koharu: Huh? So you'd just give up there?
Sayumi: For me, joining Morning Musume was my dream.
Koharu: Seriously!?
Sayumi: Right now I don't have any dreams beyond that.
Koharu: That's definitely a lie.
Sanma: Right?
Koharu: Don't you agree that's definitely a lie?
Kamei eri fan here - not sayu, not Koharu...based on the transcript above, I didn't find it offensive. I think Koharu was just surprised that sayu is just satisfied with being a Momusu. Sooner or later she's going to leave the group. After Momusu what is she going to do? What are her plans for the future? That's why Koharu asked "Huh? So you'd just give up there?"...Koharu telling sayumi that "it's definitely a lie" is just like what everyone says to his/her friends when they really wanted to get a definite answer. I thought nothing was offensive here...Or maybe we should get the whole transcript