The Fugu is a deadly poisonous dish made from the flesh of a blowfish. In Japan, these parts are eaten, but only experienced chefs (with countless years of training) are allowed to serve this fish to customers, as inexperienced people could end up being poisoned, or even dead. The chef must carefully remove the eyes, liver, and (if it's a girl) ovaries, because those are the poison parts.
Fugu is eaten because it can make people "feel romantic". Also people who want to commit suicide eat it because of the high chance of dieing after eating it.