Your senior co-worker, Tomoe, has invited you over for a dinner. You ring the doorbell Tomoe: "Hey, come on in, I've been expecting you. Oh, by the way, let me introduce you to my daughter." She brings out her daughter into the living room to greet you Tomoe: "Her name is Yui, she's 15." Yui: "H-Hi!" Yui waves at you and seems to be blushing for some reason Tomoe: "She's a really good kid, I bet you'll just love her." There's something unusual about this introduction...