Who knew? Parts of the blowfish are poisonous, but they generally cut those portions out. That is, unless your creative chef serves the poisonous testicles to you as an appetizer - while I can't attest to Japanese sensibilities, not a single fucking word in the phrase "poisonous blowfish testicles" sounds remotely appetizing. The testicles were requested by the diners, who should not be surprised that they got exactly what they asked for.