This was a recent askTRP thread
We were driving and she was texting a chuck BP guy she worked with. I know him, we lift sometimes together. We all been out together with outher friends too. But he asked her to get tacos and she said yes (no date yet) but she’s willing. She didn’t hide it but didn’t tell me until I asked. To her “lunch date” means nothing serious and it’s just getting food. She told me he is like a “brother” and she would never do anything with. Should I let them go eat? I do trust her, but not the chuck taking her out because I know he’ll try to take her for drinks. Should I just let them go?
I once stopped by a coworker's office, said hi, told her she was fine (not really, but nice waist and booty) and suggested we hang out during lunch. She giggled and denied me claiming she had a boyfriend and didn't budge. But the point is, if she said yes, I would be the coworker in the situation outlined by OP. I was offering dick and if she said yes, it means she knew what I was doing and was open to the idea of Warlock Spunk.
edit: Example 2
Did some contract work for some woman once. I told her she was cute and asked if she was seeing anyone. She said 'yes'. I asked her out for drinks anyway and she gave me her number.
By taking this thought approach (or worse, she could have initiated everything), you can see if a woman accepted (or initiated) a 'hangout' offer from a non-family male (insemination offer), it means she was willing and probably will have sex with him given some time. His cum in her pussy. There was was zero chance of it being 'innocent'. This is not acceptable and there is no second chance. Silent demotion to plate or soft next. No explanation, EVER. Immediately find a new girl which you should already have in your phone pre-heated.
1) She was texting him, which means she gave him her number and is using this line of communication for non-work related reasons, to 'hang out'.
2) She was hiding it and wasn't calling it off.
3) AND he knows you or has hung out with you? Nigga, please. This guy is trying to weasel his way into that pussy and she knows it.
A guy wants to fuck your girl, she gave him her number, used that number to secretly meet up and is continuing to do so even after, you, the boyfriend, found out?
Do not listen to any of that bullshit that comes out of her mouth to justify it. Women are not that dumb. They know what 'hang out' or 'netflix and chill' means. She's either open to the idea of sex, has had sex with him in the past, or is currently doing so. Doesn't matter your assessment of him. You know for a fact that if she goes out of the way to have lunch during non-work hours with him, he wants that pussy, and she's up for the idea of giving it to him.
Women do not meet up with men 1-on-1 while in a relationship for 'friendship'. You've been listening to women and bluepill folklore like you're not supposed to.
Q: So do you just let her go with him?
As one of the commenters said, you don't 'let her' do anything. She's made up her mind and wants to see him. A girl that values your relationship does what the girl did to me, deny their advances and makes no contact. She can go, but "no gf of mine goes out with other guys."
Any command on your part to prevent her will be viewed as jealous even though it's justified. She will double down on her denial and do it anyway, if only out of spite. Or she will agree and do it anyway, even with another guy (you said she couldn't go with that guy, but THIS guy is different because "blah blah hamster blah blah woman woman blah blah blah").
This is likely not her first "lunch" while with you.
Don't try to control women, it's a waste of time and you will fail. They're gonna do what they please when you're not around.
You know what to do. Now get to it.