I Came Back Without Memories, They Came Back with Regrets

To cheer up their depressed adopted daughter, Ashley Reid, my parents don't dare to treat me nicely. They've even locked me in a pitch-black room more than 700 times, just to put a smile on her face. At first, they feel guilty toward me. But eventually, even my older brother, Liam Reid, who used to care for me the most, treats it like it's all perfectly reasonable. When Ashley's depression finally starts to ease, I work up the courage to kneel and beg them to seal off that room for good. But at her birthday party, simply because I'm wearing the only T-shirt I own, she starts tearing up and asks my parents if I don't like her. My parents and Liam rush to comfort her and, yet again, lock me away in that dark, endless room. "Summer, you're her elder sister. You have to be more considerate of her feelings." "If you hadn't insisted on wearing something so tacky for her birthday party, she wouldn't have gotten so upset." "You've gotten used to it after all these years, right? One more time won't matter to you." I curl up in the corner, gripping my hair, unable to say a word. Three days later, they finally let me out. They remind me not to upset Ashley again. But I just stare at them blankly. "Sorry, who are you?"