Self-whore

A person who devotes a large amount of their time to themselves for any reason

"Damn, Adam has stopped hanging out with us and sits plays video games at home all day."
"Yeah, what a self-whore'

" Wow, Katia has been studying a lot recently, she's becoming a self-whore"
"Good for her! I wish I knew how to focus on my work as good as she does"