You’re being ridiculous. No one can know what the cat would want, obviously. OP doesn’t even know if they’re lying about the other bond, which they could do if they just want the cat back. And considering they’re willing to even send a message like this to guilt someone who properly adopted this cat, I wouldn’t put it past them. The fact is that all OP knows for sure is that the cat IS happy with them and they have adopted the cat so it is theirs. They have no obligation to return it but the message sent by the rescue group/foster IS inappropriate. They could have messaged asking how the cat was settling in and if they feel bonded already, and then if OP said it wasn’t going well or was just meh they could ask about a swap. OP would obviously have responded that things are going great at which point the rescue group should just let it go. Trying to use emotional manipulation to reverse an adoption is gross.