It's just a
mouse . :p
But, seriously, I've been there. I was once driven to use poison.
When I moved here in 1998, I was moving in with my father who had just begun to experience living on his own for the first time. It didn't take long for me to realize that we had a mouse, and that my dad was feeding it.
And I don't mean just leaving food out.
He was putting food in a little dish and setting it next to the radiator in the living room, "for the mouse." I was living upstairs at the time, so I wasn't sure if I'd be affected. But, one day, I saw a tiny chunk was bitten out of a button on my remote control.
My REMOTE CONTROL!
After that, I had a little talk with Dad. I forced him to get a cat, and that was the end of the mice.