The first time your unfaithful

The first time you're unfaithful won't be the worst time you're unfaithful. It will probably just be a kiss with a stranger when you're on the piss. And the next time, if you might fuck him or, even worse, you might suck him. I know I said I'd want to know but that depends how far you go. How do you think we will adjust now we've incorporated lust? And will you put my trust to test if the shagging's not the best? You said you know what I'm like... We were chatting with your sister, I was winding you up - you think I've missed her. She was fairly adamant I'm nothing but a lying cunt.
And the first time I'm unfaithful won't be the worst time I'm unfaithful. Once I've got a taste for it, I've everything to waste for it. So do you think I can adjust now we've incorporated lust? Or will I put your trust to test when my behaviour's not its best? You said you know what I'm like...