NTBT 

NTBT is a text/chat/IM abbreviation that stands for "No Tell, Bro Talk." It is generally used as a preface for sensitive information, especially in regard to something that a bro would not want his girlfriend to know about.

Text sequence between two bros.

Bro 1: Dude, you'll never believe what happened last night.
Bro 2: What?
Bro 1: NTBT.
Bro 2: Of course.
Bro 1: I totally fucked my girlfriend's sister.
Bro 2: Nice.

NTBT by Pooh Richardson June 12, 2014

ntbts 

Abbreviation for "not to be taken seriously."
Sometimes typed in a manner to resemble html code, the phrase is used to convey tone of voice in forums or message boards when a poster wants to imply a joking manner in their post, though not necessarily a sarcastic one.
It is similar to "oaj" or "only a joke," </teasing>, </joke> and </joking>.
<> sometimes displayed as .

The poster's reply said, "Now that I know that about you, I'm going to put you on ignore </ntbts>" but I didn't get upset, because I knew that person was only teasing.

ntbts by Stori May 31, 2007

NTBTFW 

Not The Bitch To Fuck With

Person A: I heard she was talking shit about you.

Person B: What? UGH I'M SO MAD IM NTBTFW.

NTBTFW by noahbb March 3, 2009