Chapter 1 My sister is weird enough

I can't remember when it started, but I noticed that my sister is very strange

But maybe I might be the strange person

Before I remembered it, I probably hadn't noticed my sister's strangeness at that time, after I grew up a little, I realized that my sister was really strange enough

When I wake up every day, there will be an extra stranger in my house, but the definition of stranger only exists in me because this stranger is my sister

Yesterday's sister disappeared, replaced by a new sister

My sister’s personality, hairstyle, height, face, age…

Everything you can see will change

Simply put, my sister became another person, someone I didn't know at all

But my parents, everyone around me, didn't notice this, only I noticed that my sister would become someone else

But even though I became someone else, my sister is still my sister

So, is the strange person actually me?