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Oh, Ernesto.
This is Ernesto, the special salticid. He was a male red-back jumping spider (Phidippus johnsoni) who voluntarily followed (and stayed with) me for two months (August-October) until he died naturally of old age.
Ernesto would hang out with me anywhere in the house, as well as follow me to the bedroom every night when I slept. I helped feed and entertain him. Creepy? Immensely. But also way too awesome not to love.
Here he's getting bitchy after exploring outside and coming back in for the night. If you look closely, his fangs are drawn forward. Because he's a Bad Ass.
More Ernesto here and here.