From: AlphaWhelp | #011
I'm 100% certain the crystal dragon is unavoidable. it's part of the story that you get it.
You don't have to go to the Opera house, the scene with Sveta is seeing the vision of her brother is unavoidable, but you can go straight to the port and choose to get on the ship instead.
---
Would the 3DS be too classy to take to the toilet?