Here is the full list of all 15 Nippon Marathon achievements.
Completed Story Mode with Nishibori
Wow! First place in a Half Marathon - You're half awesome! (Player 1)
Whoa! You finished a single race with 100% popularity, that is incredible! (Player 1)
Completed Story Mode with J DARWIN
100 Shiba Inus have been startled!
Well done, you went to the effort of finding a page from Wedy's Travel Guide and then, well, you ate it.
Boo! You finished a Single Race with 0% popularity, you suck! (Well done) (Player 1)
You were declared the smelliest - Get away from me!
You chose Snuguru 20 times. (Player 1)
Completed Story Mode with Snuguru Maestro
Completed Story Mode with Zenbei
You traversed 200 meters in LOBSTER mode
Whoa! You hit 3 strikes in a row in Go-Go Trolley Bowling!
You finished a Full Marathon, what impressive cardio!
Collected all Wedy Pages and became a Legendary Backpacker