1000-7=?Of course it equals 993
From "Tokyo Ghoul> Anime Season 1, Episode 11.
YamoriTorturingKanekiWhen he asked him "What is 1000 minus 7?", and after Kaneki answered, he asked "What is 993 minus 7?", and so on, to keep Kaneki conscious. Kaneki also used this to retaliate when he fought back against Yamori.
Origin: In the Mini-Mental State Examination (MMSE) in psychology, "100-7, subtract 5 times consecutively, and write down each result" is used to check the subject's attention and calculation ability.
Means intimidation or threat. It is also often used for mindless spamming.