Does he now!
I would ask him if you can try putting it up his anus first, and if he says no or looks horrified at the very idea, ask why it is not ok for you to do it to him, but it is ok for him to do it to you?
Do not do anything you are not comfortable with ever...
However, if you do want to try, using it in the vagina is fine and should not be too uncomfortable if he is slow and gentle. Dildo's are hard and rubbery and will not bend to fit your shape, therefore he must be gentle to prevent it from being painful.
If you want to use it anally, make sure he uses lots of lubricant and is extremely slow and gently and stops as soon as you say so. Do not move the dildo from your anus to your vagina as this will cause infection, it would be best to put a condom on it when using it anally and clean it thoroughly before using it vaginally.
Hope this helps and that you have the confidence to do what feels right for you x
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