Terkel is in trouble

Terkel is an anxious and shy guy, curly-haired with braces, a kind dude in himself, but sometimes he can ignore his sister or tell her to leave, his best friend is Jason
Fiona is Terkel's younger sister, a typical little girl who is very active until she goes to school. She wants a lot of attention from her brother Terkel so that he can play with her. Their parents are not very interested in what Fiona and Terkel are doing, so Fiona can come to school or to places where Terkel hangs out, but not often.
Jason is a guy who always carries a crowbar, wears a hat most of the time, swears every other sentence, if not more often, but overall he's a decent guy.
Joanna is a dark-haired girl who is in love with Jason, but he hardly notices her. She is quite kind, but can stand up for herself.
Doris is a kind, modest and plump girl, she is in love with Terkel, but she is teased for literally everything that can be done by Nigel and Saki
Nigel is the shortest in the class, a blond with a Ukrainian accent, smokes, drinks, and swears. He's always trying to make fun of Doris, but sometimes he can make fun of someone else. In short, he's a moral monster and only friends with Saki.
Saki is the tallest in the class, he has black hair and skin almost like a corpse, he, like Nigel, pours out on others, but much less often, smokes and drinks, if you share a cigarette, peace or baked goods with him, he will respect you and maybe even start to be friends, less aggressive than his friend
Barry is a guy with glasses and a bowl cut, a music teacher who is pretty cool as a teacher, kind and fair.
Gunnar is also a teacher, tries to seem kind, has animals, but if you don't like them, he hates you, even if you accidentally sit on a spider, he will wait for the moment to kill you, in short, a wolf in sheep's clothing, curly blond