Eating only fried dumplings for 15 years
The human body cannot subsist on a single food for a very long time (certainly not something like fried dumplings). Dae-Su would have most likely died of organ failure long before his 15 years were up due to severe nutrient deficiencies. It seems odd that Woo-Jin would put Dae-Su in this sort of mortal danger during his imprisonment, since his plans require that Dae-Su survive to be released.
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