黒くろ歴れき史し

noun

dark past; cringeworthy history; something one wants to forget

Internet slang for embarrassing or shameful past events, often from one's youth, that one wishes to erase or pretend never happened. Commonly used self-deprecatingly.

• 中ちゅう学がく時じ代だいのポエムは完かん全ぜんに黒くろ歴れき史しだ。

  The poems I wrote in middle school are totally a dark past I want to forget.

• 昔むかしのブログを見みつけて黒くろ歴れき史しを掘ほり返かえしてしまった。

  I found my old blog and ended up digging up my cringeworthy history.