San

I am traveling to Japan to hike the Kumano Kodo in 2 weeks. Since the majority of the train travel will be in the first 3 days (then 6 days hiking) and the last 3 days of train travel again, I wondered if there was a flexible plan to travel 6 days out of 15 or similar to the Eurail passes? The 2 week pass seems a waste of a lot of travel days and I am conflicted between that and individual ticket purchases.