>>95490284Being a person who likes to constantly fuck with one person who doesn't find it funny makes you a bully, anon. The way Janna treats Marco would alone prove that she's a shit, but it's not just that, she constantly shows that she's simply not a nice person. Not just to Marco but to other people too. Even Star calls her a scoundrel.
It's used as comic relief, and makes Janna an amusing character precisely because she's so awful, but she honestly isn't a sweetheart or a nice person. She loves to laugh at the pain and misfortune of others, steals things, is constantly in detention, tries to pull dangerous pranks resulting in physical injury. In the beginning of the show she was just slightly odd, but the more screentime she's gotten, the more extreme and creepy she's become. You have to accept who she is.