Putting natural perverted nature aside, I'm not sure I'd ask someone for a massager (to massage with) from someone whom I know masturbates with it. But, hey, that's just me.

It would be alright if you just cleaned it before you used it.

Plastic is fairly antiseptic - no place for organic materials to get caught and let diseases remain. Assuming you have no open cuts on your skin, and you are wearing clothes, the odds of any sort of lingering disease getting into your body are essentially nil.

The chances of getting a disease from drinking out of a used but well-cleaned toilet are practically nil as well, but I still wouldn't do it.

It can be used cleanly by placing a condom or some type of protective cover on the tip for masturbation.

HimuraK24 said:

It can be used cleanly by placing a condom or some type of protective cover on the tip for masturbation.

It's principle, man, principle.