This is just a one shot novel that I'am considering continuing. It's about a girl, a boy, and a cave.

Yumico ' Yumi ' Shiraishi is a Thief. She stole his heart with no Intentions of returning it to him. There's one big catch, though. She's the missing Heiress of the biggest company in the world. What's her backstory? and WOAH! Is that a Gang?