Stalking!

Stalking is scary and something which should not be taken as a joke. In no case is stalking okay. It is invasion of privacy and space which could lead to other serious and complicated issues. Intrusions include gathering information and surveillance of pictures and other video footages. This can lead to unsafe and dangerous behaviour and other problems such as fraud on the victim’s behalf.

http://www.bbc.co.uk/insideout/yorkslincs/series7/stalking_advice.shtml