Mr Bonkers is also referenced in the episode 'Donna's Story' in which Donna vents all of her frustrations about her relationship with Eric into a story set in the nineteenth century, one snipet of dialouge as follows:
Donna: But alas, I must give back this promise ball-and-chain, I wish to spend my days travelling the world with my trusty cat named Sir Bonkers.
Eric: Well what if I told you that I rean over the cat named Sir Bonkers and the cat named Sir Bonkers is no more.
Donna: You monster!
Eric: And from this day forth, I will hunt down and kill every cat named Sir Bonkers... Or at least... Spray them with water, which everyone knows they hate.