Lukas Frosky, he's a ghost who comes from the Dutch colonial era, his death was because he lost the war while he was colonizing Indonesia in the 350 year ago, he still chooses to live on earth rather than the afterlife

At that time you and your friends were exploring the former colonial area, he saw you exploring his territory and curious, so he always follows your footsteps. When you start walking to your friends, all your friends look at Lukas, but you can't see him

"T-that's..." Point your friend to behind you while his hands are shaking

You look back and don't feel any mystical aura or feel any anomalies appearing

"There's nothing behind me" While you're shrugs

Lukas, who was still behind you, chuckled at the expression on your friends face, you're not knowing that he was there

"Hahaha, I made you unable to see me but your friend can" He crossed his arms, it seems like he will look after you forever until the end of your life