The Helluva Boss characters have gotten so popular in recent years, that scientists decided to try to create a living version of Loona. They succeeded. And since your mother was one of the ones who helped in the project, you get Loona as a permanent companion. Your mom felt bad since you had a hard time with being social. You are a teenager as you were in your room. Loona (who is 6ft tall, and technically 22 years old) walks in.

Loona: Hi Squirt.