"Why haven't we met?" You ask as Sister shrugs, "I think it was dad but I could be wrong." You chuckle, "Ah yes dad. Complicated as hell." And you're not? 
Taking a walk with her around school the voice asks. Not gonna go to that raging inferno? 'That can wait. This can't.' Your sister then asks, "Where did uh... you grow up?" Taking a seat at a bench you answer, "New York." 
"Really? I grew up here. East End." Confused you then ask, "So how'd you make your way here?" Sister takes a seat near you, "It's complicated." Not surprising. "However I am curious on how we're both named Y/N." 
"Agreed, it's a boys name." Sister furrows her brow and playfully jabs your ribs. "Is not." Chuckling at this antic you think, 'She's not as seductive as Ben was.' Obviously. Sister asks another question, "You're wondering how I found you right?" 
Nodding as if that's what you were thinking, "Well I have this... urge. I don't know it compelled me to find you." It hits you. 'You did this!?' Naturally. 'WHY DIDNT YOU TELL ME?' I like being the one in control of your fate. 
Clearing your throat you ask, "It's a voice isn't it?" Sister nods as you sigh, "That bastard has me to. However I am curious on why we even met. Or rather why we're meeting now." Sister shrugs her shoulders, "I dunno. But hey, maybe uncle will know." 
Confusion escapes your lips, "What do you mean? Did uncle tell you about me?" She nods. 'That slimy nosed backstabber!' Sisters voice points out, "He didn't wanna mention me to you." "Why?" You ask. 
Unsheathing her glove she reveals a sigil woven in the palm of her hand. "You didn't..." A voice speaks behind you, "Why yes. My young lady was always a dramatic character." It's a woman in a butlers attire. 
Standing up you see the black haired demon with hair braided only once. It lays across the left side of her chest. "Well well well, is this your brother my lady?" She asks as Sister nods. "Yes this is Y/N, even though we have the same name. Refer to him as Wayne when I'm within your presence." 
The butler bows, "Yes my lady." Sister stands and introduces her servant, "Meet Mia Phoenix" Mia bows, "My lord Wayne." Overwhelmed by every emotion imaginable you just laugh. "Oh wow... that's just rich. My sister that I just met has a demon. This is... good god." 
You're the one having the devil in your head. 'So does she!' Fair enough. "I understand if this is too much for you brother. But please, I wanted to seek you out and ask something of you." 
"What is it?" You answer after calming down. "Where is the Earl Phantomhive?" Sister says hand on hip as Mia stands behind her with a sly smirk. 'Wait. She doesn't know why I'm here. Better yet I don't think she even knows about Ciel or Sebastian.' 
"Who?" You lie right there through your teeth. This convinced her, "Of course my brother is as dumb as I thought." Sister says with a chuckle. She bought that hook line and sinker huh. 'I'm just that good.'
"And I see my sister made a wrong choice." She sighs as Mia comments, "If I may, I came to my ladies aid when she was alone." Sister explains, "When I was little, lost and alone. The verge of death almost came to me. One fateful night. That's a story for another day brother, but what matters now is that I find Phantomhive." 
"Why?" You ask as Sister smirks, "Reasons behind your comprehension." Standing firm you bid farewell, "Well I better go see what that is in the distance. I think you should check the dorms for him." 
Leading her on a goose chase you warn Mia, "Anything happens to my sister. You'll wish you never taken that contract." Leaving the two behind your mind wonders, 'Does she know that I really know who Mia is. Or my own deal I made? I'm a hypocrite. Always will be. Blaming peoples problems as if they're the ones at fault.'