What exactly happens when using UR3 materials anally without a condom? Is it possible to do this safely? Are we mainly talking about discoloration and difficulty cleaning or is it a serious safety issue? I'm not intending to share the toy.
It is a porous material, so you can only clean it so much/well. I would look around for condoms that have water based lube in them (look around on-site) and are of a compatible material. Don't forget to check the product material guide for UR3 to see which materials you can use with which.
You can use them without a condom, but it's not a good idea. UR3 can leach chemicals that your body picks up, and porous materials can absorb things that they come in contact with as well as having bacteria grow in them.