I took Shin Nihonkai Ferry from Otaru (Hokkaido) to Niigata and tried their Suite for the first time. It was amazingly comfortable. *The price is depending on the season.
More overnight ferry trips in Japan
Splendid! A Brand New Japanese Overnight Ferry Experience from Osaka
https://youtu.be/0VRtiRvxxfk
Beautiful Trip by Overnight Ferry in Japan | Kagoshima to Yoron
https://youtu.be/OZsXZzVM1Tc
My second channel: Solo Travel Japan / Food Tour
https://www.youtube.com/channel/UCGM2TfYnu_evkx38L8eIapw
Otaru and Niigata Food Tour video are coming soon
Thanks for watching