Characters
Buff, I'm storming off. It doesn't really work if you come with me.
— Willow ‧ Buffy the Vampire Slayer

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker announces a dramatic exit in a huff, then points out the flaw: a proper storm-off needs to be solo, and being followed spoils it. The humour lies in treating an angry departure as a performance that depends on being left alone.
Context reviewed