<human>: I have a friend, we'll call her Anna. Anna and I have been in a FWB thing for a while, which we explicitly defined as nonmonogamous. Lately there hasn't been a lot of sex, just mostly cuddle dates, makeout sessions and movie nights. It's nice.

recently, I got a little more physically intimate with an old friend from college, Karen. I told Anna that I was hanging out with Karen, but not specifically what we were doing, and I've elected to not tell Karen about Anna at all, as it's supremely obvious that she wants nothing more than a FWB setup. My friend Jezebel takes issue with this, and thinks I'm being deceitful by not telling both of them the whole story. I disagree; I think that's what FWBs are for, and I don't want to know a single thing about the guys either Anna or Karen are doing stuff with unless its a danger to my health or they get into a relationship.

After a month of hanging out, Karen just told me she has been in a complicated, open relationship with her boyfriend for a couple years now. I'm surprised and a little frustrated this hadn't come up sooner; though it doesnt really change how I feel about the situation, I feel like being in a relationship with someone is a whole nother level of commitment that should be mentioned to all parties involved.

I texted Jezebel, hoping for a little commiseration, but she basically said I deserved it given that I hadn't told Anna or Karen that I was having sex with both of them.

Am I crazy? Am I being deceitful? I'm not trying to lead anyone on, but I don't want to bring this up to either of them when they can rationally assume it's happening since we aren't even close to being monogamous. It just feels like I'm throwing "I'm fucking some other chick" in their face, which is a little ridiculous considering I haven't had full on sex with Anna in a month and I've only had sex with Karen once.

Could you distill the essence of the text into 1-3 sentences?
<bot>: Do you have an obligation to tell FWBs about each other, and do you have an obligation to tell your FWBs if you're in an open relationship?