What is a play that relates to an emotion (e.g. happy, excited, surprised, sad, etc.) about five friends?
The criteria for the answer to this question is very vague, but, with that said, the play by Samuel Beckett "Waiting for Godot" is one of the greatest plays ever written and it has five characters who have continuous dialogue. I know of no play that is "related" to any specific emotion. Plays, full length ones, at any rate, are written to express a myriad of emotions. There is often a predominate emotion that sets the tone for a play, but you have not said what the emotion is that you wish to pinpoint. I would be better able to serve this question if I knew the purpose of this assignment. It sounds as though you are looking for something like "The Breakfast Club," which is a film, not a play, in which, "five high school students, all different stereotypes, meet in detention, where they pour their hearts out to each other, and discover how they have a lot more in common than they thought." (That last is a quote from the movie trailer.) The film script for this is, I believe available online, and is perhaps what you are looking for.