While it is not harassment to seek the return of property that is legitimately yours, continuing to call someone that refuses to return the property is not going to resolve the issue.
If this person refuses to return the property, you should file suit in civil court for the return of the property. (Small claims court may apply, depending on the property and the jurisdiction.)
Additional: Also, under the criminal statutes of your jurisdiction, and depending on the "property" being claimed, you may also have grounds to report them to law eenforcement for a criminal offense 'wrongfully converting property belonging to another to their own use,' (or similar wording).
CAUTION: Do NOT expect law enforcement to become embroiled in any civil dispute over items personal property.
No. Staring is just rude behaviour. For someone to be harassing you, they have to be contacting, tracing, following, stalking or intimidating behaviour, particularly if you have told the person to back off. Harassment can be a form of stalking, which is illegal.
Tell him that you are not interested and warn him to leave you alone. If he doesn't, then report him. Unreported harassment could turn into stalking, or worse.
Stalking is unwanted or obsessive attention by an individual or group towards another person. Stalking behaviors are related to harassment and intimidation.
You can contact the police if you are being stalked. In most countries stalking is illegal and includes acts of harassment.
The are interested in stalking their prey
Proving harassment can be very difficult. It depends on the frequency of the behavior. For instance, stalking is two or more unwanted encounters with the person. Threatening letters, emails constitute harassment, too.
If a cult consists of at least one member, it appears there may be.
I'm not sure about that, but it is stalking, so you should probably stop.
Whether or not someone is single has nothing to do with any charges that would come about with stalking. The person who is doing the stalking can be charged with harassment or with stalking. If found guilty of either crime a fine can be handed down and jail time can be given.
A break-up and a restraining order.
No, an obsession are intense, inner feelings. Stalking is an act of following, tracking, spying, harassment, and physical violence. Stalkers tend to be obsessive but, definitely, not all obsessed people are stalkers.
Restraining order/no stalking order. Requires proof of harassment. It will require the person to have no contact with you and stay a specified distance away from you.