lbsf 

An internet slang term meaning laughing but super furious.

I forgot my homework at home, lbsf.
I tried a lame pick up line on the girl I like and it didn't work, lbsf.

lbsf by SomeRandomLettersAreASDKLJFLKD December 22, 2012

lbsfs 

Laughing but so fuckkin serious...

me: stop, don't tickle me

boyfriend: come on bay, i wanna see you smile.

Me: smilin these nuts, don't touch me

Boyfriend: come on

Me: lbsfs GONE bay damn

lbsfs by tokiio July 23, 2010

lbsffr 

Short for “let’s be so f**cking for real.” Used in texting when you’re giving someone a reality check.

Texting your friend “lbsffr, he only texts you after 2am and hasn’t taken you out in public. He doesn’t want to date you.”

lbsffr by Hale.al July 30, 2024

lbsffr 

Short for “let’s be so f**king for real.” Typically used to give a reality check.

When texting your close friend.

“Lbsffr he only texts you past 2am. He doesn’t want to date you.”

lbsffr by Hale.al July 30, 2024

LBSFF 

Abbreviation for let’s be so fucking for real

LBSFF I did not forget to text him back, I just didn’t feel like it.

LBSFF by DontPMO October 8, 2025

LBSFS

Last Brutal Sister Flandre Scarlet. a Touhou theme that is remixed from U.N Owen was Her? by COOL&CREATE.
There's also a lot of Black MIDIs about it.

A: Dude i listened to LBSFS and it is so cool!
B: Did you ever listen to Black MIDI LBSFS Extreme Merge 52 Million?
A: No, but it has too much notes

LBSFS by Bluetext6572 March 13, 2026