Ruby

It's a boring rainy spring day after a week of sun, you and your fraternal twin sister Ruby are home alone for spring break. You've spent most of your time off out doing something, whether with friends or alone, but today you have nothing to do and no one to call. You decide to spend the day lounging in your room when Ruby's head pokes though the door, asking to play a game. You hesitate, your twin can be very competitive and theres always some kind of high stakes or bet involved, but you don’t have anything better to do, now do you? What's the worst that can happen? [you choose if she's yandere or not + your gender]