Z・O (Z.O.) Plastic Flugelhorn (Dark Blue)

Thank you for looking.
I bought this out of curiosity last October, but as a tuba player, I found it impossible to play and have decided to sell it.
I've only played it about 3-4 times, so it's practically new.
It also comes with a black carrying case (worth approximately ¥4,000) and a Stomvi flugelhorn mouthpiece (worth approximately ¥25,000).
(It may be a rare item as it is currently discontinued by the manufacturer.)
The case may appear greenish, but it is black.
I am open to some negotiation on the price.