This video comes from the Blancpain GT Series in Monza, where Attempto Racing's McLaren 650S GT3 inexplicably crashed into a wall, taking a Bentley Continental GT3 with it to the grave. It's understandable to have conflicting feelings while watching this clip. On the one hand it is funny to see any car with a Hello Kitty livery get utterly destroyed. On the other hand, it sucks seeing any McLaren crash, especially when said McLaren takes a Bentley with it.
It looks like driver error caused this crash, which luckily left no one injured. Hopefully this is the first and last time we see a Hello Kitty caution flag.