Rat Pack
Depending on where you live, what time of year it is and if there is food around, you might have a rat problem. And if there is a full-blown infestation, then that might mean you need t get your landlord involved because there is probably a whole lot more where that came from.
I’m sorry, did this landlord think that his tenant was just sharing some fun, exciting news with their landlord about how they got new pets? The complete lack of understanding and rude tone is definitely not what you want from your own landlord.