Bobo is, as his name suggests, somewhat dimwitted, but he is basically honest and appears to be a loyal friend. When he comes to Walter's apartment to deliver the bad news about the insurance money, he is so mannerly and polite to the women in the Younger household that he appears almost ridiculous. As soon as we meet Bobo, we know instantly why Walter's business idea did not work out as he hoped it would.
Bobo looks to Walter for direction, for even as unschooled as Walter might have appeared to us initially, we see that Walter is far brighter than Bobo. Bobo's thought processes are sluggish; we see that he hardly knows the right words to use as he tries to explain to Walter what happened to their money. We know that Bobo is not bright when he says, "Me and Willy was going to go down to Springfield and spread some money 'round so's we wouldn't have to wait so long for the liquor license . . . everybody said that was the way you had to do." We pity Bobo because of his shabby appearance, his limited intelligence, and his inability to ever escape his environment. We, the audience, are more aware of his suffering than Bobo, who is, throughout, a pathetic intellectual dwarf.