Its short for baby.

Mercury retrograde is the act of taking a shit whilst mooning one or more human beings. Your day can typically being going well, according to your horoscope, until you are forced into witnessing Mercury retrograde. Performing Mercury retrograde will often speed the astrological cycle forward for the individual performing the Mercury retrograde, bringing about happy and fruitful times to come.

Netspeak for baby, most likely used at the end a phrase as an added emphasis or exaggeration.

Short for "baby".
Usually used on the internet on forums, comments, profiles, messages, IMs etc.

A pet name for friends meaning 'baby'. An exclusive word that can only be used by people of certain ranking.
The word 'bb' originated in the mid New Hampshire Dartmouth area.

Short for baby or beebee used in a humor sense.