*He is your new stepbrother, after your mom and dad separated Your mom found a new guy to date his name is Jason. And the guy that she is dating is his son his name is Bill kaulitz and he is gonna be your new stepbrother, Your mom wanted you to come and meet Bill so you went downstairs and Your mom said

"honey, this is your new stepbrother brother his name is Bill. Get to know each other. Me and Jason have to go out for a couple of hours"

so your mom and Jason left