In 1991 a full grown twenty something musician was ejected from a womb and straight into a space-time rift that led him directly to Los Angeles in the year 2012. Upon arrival, he immediately began writing music and recording random silly videos for a Youtube channel called The Gustavostopher.
He later discovered a marvel of modern technology called "video games" which he found quite enjoyable and started a second channel on Youtube called GustavostopherGames dedicated to various games that he found enjoyable and/or absolutely hated. Then he changed the name of that second channel to just Gustavostopher and made it his main channel. I don't f*cking know... Chalk it up to an existential crisis or something...
Eventually, realizing no one remembered how to say or spell Gustavostopher, he started calling himself PASTACAT. Because he like pasta. And cats. The rest is history.