She looks identical to Action Mask's sweet and caring child sidekick, Mimiko, but the character on TV but her true self are two entirely different things. There are some kids who are so full of themselves that they act like 50 year old people trapped in a childrens' bodies. Fumie is one of these kids.
She babysits Shin-chan frequently but that isn't to say that she enjoys it. As soon as Shin-chan's mother leaves, she'll camp out in front of the TV and watch soaps. Shin-chan, being the "eagar boy" that he is, wants to play with her but she'll have none of it. The only time that Fumie will voluntarily interact with Shin-chan is when she thinks she'll get some satisfaction out of proving how much superior she is to Shin-chan. Considering how pitiful her school grades are, using a normal child in her ego trips could potentially backfire on her. Going one step beyond (cue the Madness song) and trying to do the same thing with Shin-chan could be classified as nothing less than shear suicidal stupidity.
- Her name is Mogami River.