Japanese Abbreviations

[Iwark]

みんなさん、こんにちは。お元気ですか？In this thread, I you will be showing me some Japanese abbreviations. Not CM, not OP, not ED, not BGM, not ORZ. Just give me the ones I'm not familiar with like OTL and the ones from www.nicovideo.jp. If you know one can you please do it for me?