A person who ends up with no social life because of excessive use of Tumblr.com.
Derived from Cinderella, who has no social life because she has to clean up cinders.
"Hey, check out that hot chick! Go ask her out!"
"Nah, she's a freaking tumblrella; she'd say no."
"That tumblrella would rather stay home and reblog cakes and animals than get laid."