English is my second language and I did not want to sound rude. I meant 'the guy that is supposed to be the biological father and he is not but he doesn't know'. In Spanish, we have a very rude word for these men: 'Los cornudos'. I love the conciseness in languages but I don't like to sound rude in HN. Sorry! ;-)
"partner" would be the right word for where you have used "couple" here.
Yes, you are right. Thank you!
Just for some balance, let me say that, as a native speaker, I got the point, even though the usage is not quite conventional. Logronoide, if I could write a second language as well as you write English, I would be very pleased with myself.