A/N: I came up with this as I wrote. I wanted Kali to choose an awesome name... But she can't just name a kid like that and not be considered evil... So I gave her a way of naming the kid :3 Hope you like it. Please let me know what you think!
Cas sat down. He had been passing around the room for what seemed like hours.
"Why is it taking so long?" he asked himself.
He was waiting for his brother to come and tell him about his nephew. Ever since Gabriel knew he was going to be a father he dragged Castiel into the journey with him. So here he was, in the waiting room, alone, waiting to know if his nephew was ok. And he also, wanted to know if his sister-in-law had picked a name for the baby yet. Once she found out she was pregnant she started wondering if the baby's name should be this or that, and Kali wouldn't ask anyone for help, and if anyone (even Gabriel) tried to tell her a cute name, she would just glare at him/her/them and tell them –in a not so nice way – that when they were the ones pregnant they would get to choose the name.
A few minutes later, Gabriel came inside and beamed at Castiel.
"My baby is a beautiful baby boy, Cassie."
Castiel smiled and got up from his seat and went to hug his brother.
"Congratulations, brother. Has Kali chosen a name for the little boy?" Cas asked.
Gabriel nodded.
"His name is Lucifer." He said slowly. "She said she loved the cat so much that she had to name her son after him."
Castiel tilted his head.
"Cat?" He asked, clearly not following.
"From Cinderella. That cat that screws with her and the little rats that help her." Gabe explained.
"Oh! I remember him. He was strange."
Gabe nodded again.
"She says he's adorable and that his name is now our kids' name." Gabriel said weakly.
"So… Now it's up to us to make him better than that cat." Cas told Gabe with a smile.
"Yup. We need to teach him that the best things in life are pranks and candy!" Gabe agreed returning the smile.
Cas followed Gabriel to Kali's room and looked at his nephew.
"Hello Lucifer! This is your uncle Cas… I will help taking good care of you." He told the little boy, picking him up from the crib and carefully placing a kiss in his forehead.