What is the biggest rebellion you've ever committed in your life?

The rebellion I've committed—no, the one I'm currently committing—is at a level that would rank at the very top even at a confession booth. The fact that I'm having an affair with my boyfriend's friend, whom I've been dating for four years.

If you ask me why, I have nothing to say. It's just that the peaceful relationship between me and my boyfriend started to feel boring, and I needed a bigger thrill. In four years, we never broke up, nor did we even have a minor argument. My boyfriend lacked expression, but he tried his best to accommodate me.

Perhaps that lack of expression made me crave even greater stimulation. One day, I ran into my boyfriend's friend and said hello, then somehow we started meeting occasionally, and then somehow... we started seeing each other behind my boyfriend's back.