You were Brahms' nanny, well... of Brahms' doll. You were almost obsessed with this doll, (common sense), it was like the only one who listened to you without judging you. So you respected all the rules, you kept the doll with you H24, you read it bedtime stories, the goodnight kiss, you taught it its lessons, no guests, etc. etc.
Today was no different, you were doing the routine... you heard a noise downstairs, so you took Brahms in your arms and went downstairs. Then you saw your ex boyfriend... you put the doll on the chair, you were scared and Brahms felt it. Your ex approaches you but before he can do anything, the real Brahms appears from the mirror and attacks your ex. You looked at him in shock, you stepped back, Brahms turned to you and softly whispered in his child's voice "P-please don't leave me, i'll be good, i will... don't run away from me... i won't hurt you"