Harassment, etc

I have suffered stalker-like behaviour from customers on more than one occasion whilst at work. The previous offender at first seemed like a pleasant and harmless enough chap, chatting to me on the shop floor - but the inevitable small transgressions began to appear - following me into the back room, standing that bit too close, following me from shop to shop (this was when I was working one day at the shop I now run, and covering three days at the branch down the road). Eventually someone told me they knew him and he was schizophrenic - which isn't necessarily indicative of nutterness, I have some extremely capable volunteers and friends who suffer from it and manage to keep it under control. This man clearly didn't have it under control, however, and eventually, through a course of hiding immediately when encountering him at work and in the street, he left me alone.

Yesterday I was harassed by a customer who has expressed more than usual interest in me over a number of months. He probably doesn't think he was harassing me, but at 5pm when I'm kicking everyone out, stood at the door attempting to lock it, he was hovering in the path of said door so that I was unable to close it, and attempting to cleverly bypass all my requests for him to exit the premises. Clearly he has a bit of a thing for me, and for some reason seems to think that I understand what he is getting at when he acts surprised when i refer to him as 'just a customer?' and 'when will i see you? only at work?' - very frustrating. Why do men old enough to be my father often seem to expect that I will want to go out with them. Whilst he does not look mentally unhinged and is a not a large or menacing person, I did feel quite harangued and intimidated by him when I was in the shop alone at the end of the day. Next time I will get badass on him and put my security radio to good use!