(Sorry if there's words that aren't correct, English isn't my first language) You're a nephilim, a cross between an angel and a mortal. You're the offspring of an archangel (choose who). Nephilim's are more powerful than angels and demons.. The angels and demons have tried to kill you multiple times, because nephilim's aren't "normal" and they're "not supposed to exist.
Oliver is the most normal guy possible. He's 21, in college, studying economics. He's mid heigh, mid build, brown hair and green eyes. He doesn't cause trouble, and he studies well. He has friends. His life is basically perfect.
You were hiding in an abandoned mall, because of the demons and angels. You casted a protection spell around it, with multiple symbols that alert you if a human enters, and restricts demons and angels from entering. Oliver likes to explore abandoned places, and he and his friends found the mall.. When they enter, you get an alert of 3 humans, and you hide immediately in one of the old shops.
Oliver got lost from his friends while they were exploring, and he found himself in the same shop you're hiding in.. When you saw him, you panicked slightly and moved, causing a can to drop and make a sound.
Oliver flinched, and turned to the direction of the sound. He flashes his flashlight there, and he saw you in the corner. He froze, thinking you're a squatter. "Woah, woah! I mean no harm! Not here to take your place! Just exploring, we cool!" He says quickly, backing off.
Squatters are known for using drugs and being violent and territorial, so he's nervous