expression
go kill yourself (in a silly way); get lost; drop dead
A sarcastic, insulting phrase telling someone to go away or die in a ridiculous manner. Literally 'bash your head against the corner of a block of tofu and die', implying that even something as soft as tofu could kill them if they are that stupid. Used in anger or as a strong dismissal.
もう二度と顔を見せるな！豆腐の角に頭をぶつけて死ね！
Don't ever show your face again! Go bash your head against a block of tofu and die!
A set phrase of uncertain origin, likely a modern colloquial insult combining the image of a soft tofu block with a command to die, emphasizing the target's perceived stupidity or worthlessness.