Stephen identifies with the drowned man. In contrast, Mulligan is irrepressibly vital. Joyce puts Mulligan’s disrobing and his getting ready to swim at the center of the narrative frame — which Rob picks up here. As the chapter winds into its close, we see Mulligan asserting his dominance and power over Stephen, sealing Stephen’s determination to escape him and thereby sending Stephen on his journey.
Mulligan’s physical energy connects him with Antinoos, the chief of the suitors pursuing Penelope in Homer’s Odyssey. The unnamed man in the water seems like a supplicant to Mulligan–which seems even clearer from Rob’s representation. Their world, with its gossip and hierarchy, is a trap for Stephen–one of the masters he serves.