[Z_lastname]

I know this thread is old but I thought I'd chime into it again~

Just earlier today I tried this for the first time (however I am a transgender man, and have a vagina, so not anal birthing). It takes some trial and error to get it quite right, ie something big enough that it doesnt fall out but not too big. I'd recommend something with minimal edges also, especially if it's something like a plastic bottle be careful any ridges in it could cause pain/cutting

Definitely tie a string to it! I cant imagine having to explain to my roommate that I need a lift to the hospital because I have a shampoo bottle stuck in me. As mentioned already though both anuses and vaginas have the muscles to push things out so you should be okay!