Very interesting concept, I am myself interested in text games for social behavior understanding and improvement via role-playing. Clicking to change lines as if following one's thoughts, and correct the email live, instead of picking among several options displayed at all times as usual, was a nice touch.

It's also clever that the generic, vague lines apply to a broad range of context (within a given category: company, couple, friend talk...).

It is mostly serious with some funny lines you can pick, like some you really don't want to apologize. And changing point of view to accept or reject was also interesting from a role-playing aspect. I myself rejected my first emails then started accepting them, I suppose I improved over the game!