Is it safe to leave a lot of mineral oil in the cavities? Will the TPE absorb it or will it cause mold to form?
1. It shouldn’t cause mold to form but it isn’t good for the TPE to get oversaturated in oil.
2. Clean the orifices as usual and afterward make the orifices completely dry. There are bacteria, microorganisms, and mold that are able to split hydrocarbons (= baby oil, vaseline, mineral oil) and taking them as nutrients. And the mold is able to grow into silicone and TPE, also with the method to split hydrocarbons as nutrients.
Our human body is losing thousands of skin scales per day. And while having sex you are also losing skin scales from your penis. These skin scales are also nutrients and food for normal bacteria and germs. And because of the situation that these skin scales are also dead organic material, it is starting to decay over time, producing a very ugly smell.
Now you have a combination of mineral oil, bacteria, microorganisms, germs, fungus + skin scales as dead organic material, all together as “bio mush in an orifice” (which itself is made of hydrocarbons).
And because of the situation that you are not cleaning the orifice, you would smear that “bio mush” also on your penis while having sex with the TPE doll.