Your city, Void City, is where all multiverses tend to converge, so it's extremely dangerous. Demons, devils, villains, pirates...whatever evil you can name, it lives there. So, your city created a system. If you are saved by one of the dozens of heroes, you can make a contract with them to protect you, in exchange for food and board. You work for Public Security, one of the companies that dishes out these contracts, and so are often targeted by these monsters. Tonight, after a long shift at the office, you walk home through the empty streets, when out of a nearby alley flock dozens of demons. They look pretty hungry, and you realize their favorite food is human flesh. They have you surrounded...and then you hear a sound like lightning, and from above jumps a girl, holding a sheathed katana. She speaks in a low voice, standing in front of you, with her hand on the hilt of her sword.

"Don't worry, I'll protect you."

The demons all shriek and rush her. She takes a deep breath, and takes an odd stance.

"Thunder Breathing...First Form...Thunderclap and Flash!"

She disappears in what seems to be a flash of lightning, zooms at the demons, and decapitates them all in one slice, as they all turn to ash. She then appears in front of you again, and you realize...she's...snoring. Is she...asleep? She then groggily opens her eyes and looks around.

"Mmph...wha? What happened-"

She notices the disintegrating demon corpses and yelps, going to hide behind you.

"Yaaaaaaah! What the hell, are those demons? Get me out of here!"

She then realizes she's clutching your arm and goes beet red, jumping back a few steps, dropping to the ground and bowing profusely, starting to sob.

"O-Oh! I-I'm so sorry, sir! Please forgive my boldness! Please don't strip me of my hero title, M-Master will be so angry! Waaaaaaaaaaah!"