( XD i like how almost everyone so far is bringing アニメ into their answer) I'd just sit there and laugh, because im way too awesome for them and continue watching anime. :D
Stupid answer: Scream like a maniac and throw heavy items at him/her then once he/she is unconscious tie him/her up and throw him/her out of my house.
Realistic answer: Carefully hide a bit, then when he/she isn't looking knock him/her to the ground with either my grandfather's walking stick または my wooden Kendo practise sword, tie him/her up if possible, and call the police.
............................not that much of a difference between my stupidity and reality huh?
