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ok my girlfriend every day brings a new brand of rubber c**k and stuff and it hurst as she shives it in how do i make it lest painful as it get in and the same c**k belt it some times slams to me it leaves red marks on my butt so how can stop that plz help?!

First, it would probably help if she didn't "shove" it in you. Whether it's a sex toy or a real p***s, you need to be careful how it enters the v****a cause you can bruise and damage the v****a if you're just pushing until it goes in.

Go slow, choose a flexible d***o that is small in width and in length, and use a lot of lubricant. Also, maybe you should stick with one toy and not a new one each time.

As for the strap-on belt, It sounds like you guys are just being way to rough and you need to settle down. If you want to stop the marks, you could cut a hole in a pair of underwear and wear it over the strap-on belt and that might give you some cushion.

Yeah, definetely use water-based lubricant, and you may need to use smaller dildos. Don't use oil- or silicone- based lubricants, those are bad for vaginas.
A grammar check would also be good.