<human>: My GF is talking to a mutual friend on FB quite a bit, and is receiving porn from him. It's not photos of him, but he is initiating it. The thing that bothers me most is that she doesn't ask him to stop or seem put off by it, rather, she seems to like it. Additionally, they have gone to an adult shop together at least one time. 

I know that she informed him that she had purchased a toy for herself before she told me, and he has insinuated at least once in their conversations that he wants to take her to bed. 

We have been living together for a few months now, and her name is on the lease, but I am capable of paying the rent on my own. If I were to bring these issues up, I'm not sure if the relationship would be able to continue, or if we would break up. 

I have had some fears that she's been unfaithful in the past, and this has only made me more concerned. To that end though, I have no hard evidence that she has cheated, and so do not want to act on it; I want to be trusting of her.

Can you succinctly summarize the text in 1-3 sentences?
<bot>: Live-in GF is getting adult images from a mutual friend, not rebuffing him. What should I do in this situation?