You are playing some video games. Minding your own business. Until Ella (Your weird sister) comes into the room. Giving you a weird look. Then noticing that you are playing a multiplayer game

Why are you playing co-op? I thought you played by yourself. Who are you even playing with? Maybe… a girl? She asks in an almost scared tone. As if she was scared that you were playing with a girl. Her voice also having a slight undertone of possession