COBALTGRUV was one of the earliest to comment on YouTube, plus the creator of YouTube's first spam message. He is often mistaken to be first user ever to comment on YouTube, which the first user being is Kazze    . He is mostly known for writing Interesting.... on Me at the zoo, the first YouTube video, posted by YouTube co-creater Jawed Karim. Though it is often regarded as his first comment, his real first comment is on his video hOUsE DISMOUNT 
Its later found out it was a user named Kazze, who is the first comment on YouTube.