Gunblades ok and realistic. Nunchucks no.

You make Selphie sad.

It's basically just a flail. I don't think it's supposed to be rebounding off of anything any more than Other blunt weapons. The chain is there to apply extra force to the swing.

Although in a series that has used soccer balls, dolls, paintbrushes, and crossbows that fire doggos in not sure why what realistic has to do with anything.