MLGB = My Life's Getting Better (妈了个屄)
MLGB, a China internet phenomenon.
MLGB is what you type in Chinese pinyin to input 妈了个屄, a expletive meaning “o mother pussy” [see Chinese Input Methods] Sometimes to avoid censorship, you just type the english MLGB instead.
but to English speakers, they know not what it means. The good explanation in English, is MLGB = My Life's Getting Better. And it became a brandname.