I feel this is quite a unique concept for a battle system, so thats a plus. But I think for it to remain interesting over a longer time there would need to be some more depth.
Often, you can easily discard one of the three options based on the last word, so once you get a feel for it its quite easy. I think it could be more interesting if you had the player type their own answers, but I understand that could be quite complex to implement. Another option could be to give the player a set of words they can use, and they have to build a reply with those words. You could scale damage based on how good the response is.
At the end of each battle you could give the player a chance to read through the whole battle.