An idiom that laughs at others and is unlucky at the same time.

Cynicism: To ridicule and satirize in bitter and pungent language.

Laughing at nudity in the same bath: taking a bath together but laughing at others' nudity. Metaphor means that you have the same problem as others, but you laugh at others.

Play with fire and set yourself on fire: play: play; Burning: burning. He who plays with fire gets burned. It is a metaphor for doing risky or harmful things, and the final victim is yourself.