Recently I have been more open with my girlfriend about her being with other guys. I've mainly been in the hotpast camp but as time goes on its an idea that's growing in me. Well as fate may have it, as I'm being more open with her, an old fling dm'd her. She told me about it and said they have been talking more and I was telling her how I'm not jealous and she can talk to whoever she wants about whatever.

So a week or so goes by and while I'm out at a friend's one weekend she sends me a couple nudes. She was freshly shaved and said she was feeling sexy and wanted to show me. When I get back during a conversation she mentions the guy who started messaging her again sent her body pics cause he was working out and wanted to show her his progress. I said 'He just wanted you to do the same' and she looked at me and said 'Well, do you remember the night I sent you those pictures?' and I didn't think about it immediately then it hit me. They were flirting and however the conversation went she ended up shaving and taking some nudes to send him.

The emotions I felt were ones I never experienced at the same time: I felt myself getting hard but also felt a bit of jealousy. I was turned on she'd be so horny to do that but at the same time it being real was... Intense. I suppose what I'm looking for is if anyone else knows the feeling I'm talking about and if it's something that's normal at the beginning or a bad sign?