Hello,I've watched a video of a chineese/japanise guy who filled up his bladder with fake cum. Here is the video: https://xhamster.com/movies/3114633/method_of_injecting_into_the_bladder_of_fake_semen.htmlI was wondering if there is any safe substance that can go into the bladder without causing any damage/infection to your urethra canals and your bladder.I've done sounding with long cable, penetrating the into the bladder. I also filled my bladder with air once or twice. I know how it works. I just need a safe substance to fill my bladder with (e.g. saline but it's looking like normal water)Do you have any ideas?