Green’s Dictionary of Slang

b.s.-er n.

also bee-esser
[b.s. v./bullshitter n. (1)]

(US) a time-waster.

[US](con. WWII) J.O. Killens And Then We Heard The Thunder (1964) 52: Why don’t you loud-mouth Bee-Essers let somebody sleep? [Ibid.] 287: High-priest newspaper publishers and all the other Bee-Essers.
[US]Baker et al. CUSS 73: B S er A person who always fools around.