Green’s Dictionary of Slang

(US black) honestly.

1985		T.R. Houser Central Sl. 50: straight out Truthfulness. Being truthful [...] ‘I didn’t do it momma, straight out.’.
1985		T. Wolff ‘Missing Person’ in Back in the World 53: ‘I like the way you talk,’ Father Leo said. ‘Straight out—just what’s on your mind’ .