You are expected to let others have their privacy.
Tom overhears his roommate talking on the phone about some juicy gossip.
Tom wants to know more about what they are talking about.
Tom brings up a similar topic later with his roommate.
Tom sits close to the wall, so he can continue to eavesdrop on the conversation.
Tom's roommate ends up sharing the gossip freely which Tom finds very entertaining.
Tom feels bad for listening in on the conversation.