i used to ...i loved it...but then i upgraded to a vibrator and it was the best thing i've ever done for myself
I wouldn't suggest inserting anything in the ass without a condom because I'm assuming you run the risk of infection without a condom on the object. Also, don't put anything in ass unless it's at least a manufactered sex toy. A banana could easily break off and get material in your ass you may not like to have in there.