Same here. Although he didn't made a story about me (and i really hope he doesn't), he includes me in this one role called "Worst Users":
https://www.mycast.io/stories/the-mycast-team/roles/influences/69952557
(Like, bro i ain't done nothin' to you, what's ur problem kid?)
Not just me, there's also one of my friends that got added to his "hate list" for no reason at all. And like oddjobs says, bro flips out and resorts to threats when someone called him out for his behavior.
And yea, i've also seen some of gio's behavior and from what i can tell, he seems to be immature, being annoying by spamming in the comments and he also doesn't seem to respect other people's casting suggestions, as shown when he mass downvote some from another user on one story and just want his own suggestions to come out on top only.
But yeah, i did blocked him already. It's just that i don't want any trouble involving him. Rather stay out of trouble than participate in useless and meaningless fighting.