Bullflay was a major antagonist in the Redwall book The Legend of Luke by Brian Jacques.
Bullflay is the sadistic slavedriver on board the slave ship The Goreleech. Bullflay is apparently a very high ranking crew member, possibly only second to Vilu Daskar himself. Bullflay loves tormenting his slaves. He has Akkla the ferret drum the slaves into submission, then row for as long as he wishes. Bullflay is incredibly lazy and hates exercise or honest work. The most exercise he does is parade around the slave decks, whipping them and yelling at them, and at night he will sit back with a lavish feast and snooze the remainder of the night away on wine.
Bullflay first appears when Vilu Daskar makes berth at an island colony of peaceful squirrels, killing and enslaving them, and to Vilu's amusement a ferocious female squirrel is defying him and capture. She says if Vilu is a coward who won't fight her one on one than he should slay her and be done with it. Vilu likes the black squirrel, Ranguvar Foeseeker, so he says he'll beat her into submission on the slave decks. Ranguvar meets a captive otter named Norgle who demonstrates Bullflay's sadism, that occasionally Bullflay will get all slaves to hoist a wooden beam and if any cannot do it he'll drop them overboard to be eaten by sharks or drown. Bullflay has done this countless times and is very cruel at it, and in fact he did this to Beauclair Cosfortingham, one of the main protagonists of the novel, but being a hare Beuclair didn't let drowning be the end of him.
Ranguvar immediately takes a dislike to Bullflay which escalates into hatred. She hates him so much for his evil sadism that she bites off his ear, causing him to bleed profusely and beg for his chance to kill Ranguvar. Vilu chides him. Bullflay then ups his ante and continues torturing Ranguvar, denying her food, and being extra cruel to the other slaves.
When they sink Luke's ship Sayna and take survivors as slaves, Bullflay delights in having more slaves to bully. He whips them all into submission and he sets them to work steering the ship. Bullflay, however, is terrified of the black squirrel being freed, and one stormy night by the Tall Rock formation, his worst nightmares happen and there is indeed a slave revolt. Bullflay doesn't even fight he instead runs screaming out of the galleys and up a mast in his panic, where Ranguvar chokes the evil slavemaster to death with his own whip.
Bullflay was a cruel, sadistic, and treacherous weasel who enjoyed separating entire families, with murder if need be, and gloating in watching the survivors suffer. He was one of the most cruel of the Sea Rogues. He was manipulative too, as he nearly argued with his captain Vilu Daskar, but then realized Daskar's evil stare and thus got so nervous. In fact, Bullflay was so power hungry its suspected he was even planning on killing Daskar and replacing him as captain.
Bullflay was heartless and delighted in his job when things were going his way. But, when things got out of hand and the slaves revolted, he was revealed as a pusillanimous coward, pushing innocent creatures aside just to save his own skin. His lack of strategy in these situations caused his death, as he fled into a death trap, straight up the mast, without thinking.