Harry's mad at me - I won't let him serenade the neighbor's cat

My cat's pissed at me now. He's been yowling at the lovely little lady cat in the neighborhood that's in heat - but he only yowls at the back door so I locked him in the bedroom / office with me. He is now in his window box glaring at me for interfering with his romantic intentions with the neighbors pretty little lady cat. It's so tough being a two year old tom cat in a house full of unsympathetic humans.