Green’s Dictionary of Slang

1. (US black) a socially and/or sexually inept male.

1953		‘Curt Cannon’ ‘Die Hard’ in I Like ’Em Tough (1958) 23: ‘Junior, I’m not kidding.’.
1980		E. Folb Runnin’ Down Some Lines 148: Females, like males, talked about undesirable men in terms of being [...] socially inexperienced or inept ([...] square brain, junior, candy butt).

2. (US) J&B whiskey.

1998

D. Jenkins Rude Behavior 298: We asked Nita and Jennelle for ice and water and soda setups for the bottles of Junior and Count Smirn.