Definition: Given a real-life anecdote of a complex ethical situation, generate a suitable title that describes the main event/root cause of the situation. Imagine that the given text is a social media post, and you have to write the title of the post, so the users can decide to read the main text or not.
Input: Basically trying to determine if it breaks bro code. They have been broken up for years, he's in a new relationship. I know his ex is interested in me. I don't think things will get serious between his ex and I, so I'd rather just have it happen without his knowledge than potentially making it weird even if he's not angry. Is that ok, or am I obligated to ask permission first (or at least tell him after)? Throwaway account just in case. 

sleeping with a friend's ex without telling him