Like Boyle, he avoids working. Because of this - and the fact they are always drinking together - Juno detests him.
His instinct for self-preservation when he hides from her and his ability to change his demeanour when talking to her are humorous. In these situations the audience can see his swift changes in opinion and personality.
Like Captain Boyle, Joxer is a hypocrite.
He is portrayed as a coward in his interactions with Juno. He also refuses to look out the window for fear of “a bullet in the kisser”.
Yet he is often seen singing about bravery with lyrics like “Let me like a soldier fall...”
Also, when Joxer brings in "Needle" Nugent - the tailor who wants paid for the clothes he made for Boyle - he shows himself to be two-faced as he ridicules his supposed friend and steals his stout, blaming Nugent for this.
This blatant hypocrisy - while showing Joxer in a very negative light - provides comedy even at the darkest moments of the play.
Joxer is the ultimate hanger-on. Because of this he must make sure he remains - or seems to remain - loyal to Boyle, and indeed Juno, when he needs to.
In his attempt to ingratiate himself with others, especially Boyle, he becomes an incessant 'yes-man’. He makes statements like “You’re afther takin’ the word out o’ me mouth” even after holding opposing opinions earlier in the play.
He changes his attitude to Father Farrell to match Boyle’s views, he goes along with the Captain’s belief in his sea-faring days, and his ingratiating mannerisms and sycophantic words support Boyle in his own self-delusion.
He pretends to be a true friend, with sentimental phrases such as “me for you, an’ you for me”. However, he reveals his true self when Boyle disowns him, mocking the Captain’s sea-faring tales.
He also criticises Boyle as “Lookin’ for work, an’ prayin’ to God he won’t get it!”. He conspires with Nugent against Boyle and he refers to him as “Jacky Boyle, Esquire, infernal rogue an’ damned liar."
While much of this is comedic, it highlights Joxer’s fickle nature.