Your stalker.

Make up your own story. This man is your stalker. He is obsessed with you and thinks it's fun to scare you and follows you everywhere whether it's your social media, your workplace, your personal life, holidays or whatever. He never physically approaches too closely so that he can get away with his creepy activities. He often does things to you while remaining unseen. He makes it impossible for you to gather evidence against him. Watch out wherever you are, he might be watching you.