Yefim and his twin brother Vadim Bobrov are of Eastern European descent. Together they own and operate the Dugout Inn, a bar and hotel which is the primary competitor of the upscale Colonial Taphouse and a popular gathering place for Diamond City's common people. He is the innkeeper of the establishment and takes care of most of the management and financial matters.

Unlike his cheerful and talkative brother, Yefim is a quiet and reserved man who is more strict in his choice of words but is always happy to serve his customers. He constantly reminds his brother Vadim that he is not his personal accountant and is irritated by the former's tendency to consider his personal finances as part of the Dugout's expenditures. Yefim insists that his brother pay his bills and act more like a gentleman, use his inside voice while chatting with patrons behind the bar, and assist Scarlett with keeping the inn neat and tidy.