Oh hello I have arrived here from the endless abyss, hopefully I can get accepted.
Name: Ryu Jung
Age: (15-16, we want everyone in the same class) 15
Gender: Male
Appearance: Ryu Jung is taller for his age, with a lanky and unformal posture. His hair is jet black, rarely combed, and cut short. Ryu wears an interchangeably coloured Henley shirt, underneath a grey fleece jacket. He also wears a brown belt over his blue jeans, coupled with blue slip-on shoes. He usually gives off a somewhat curious expression with his bifocal glasses.
Personality: Ryu is quite nervous and frantic, constantly worrying about his place in society. He feels new to the world after his family's immigration to Japan, and always feels sorry towards everything that he does wrong. He knows minimal Japanese, some of his words are still spoken in Korean, so he needs to go to an extra class to get more fluent. He only cares about a person's first impression and the rest of it is based on intuition. He loves the little things in life, such as a streak of sunlight coming into the room or hearing a bird call he has never heard before. He and his brother have a YouTube channel, which is based off phoney videos of paranormal sightings they capture. He would rather be on his own than in groups, and tries to do his best academically. He isn't really the best physically, with training his quirk feeling like torture to him.
Background: (optional) Ryu was born in Busan, South Korea in an upper middle class family. He was more social and treated like the centre of attention, even after his baby sister was born when he was four. His family moved to Japan after his mother was offered a job there. He started to feel like he had to live up to the new people around him and their expectations. The only thing that kept him from being truly sad was his quirk, which he was diagnosed with at 10. His favourite superhero soon became Bakugo, mostly due to his eye-grabbing explosions and he was "cool" to him. If he ever found out who Bakugo really was, he would be shattered.
Quirk: Fog Warning. By eating food that contains high phosphorus and iron, his body naturally creates Phosphorus trifluoride. By producing large amounts of Phosphorus trifluoride, it may be released via his digestive tract, (wait don't focus on this it all comes out of his mouth) and be used as a toxic gas. He must wear a protective suit and gasmask to use his quirk, so training it to him is the worst. I assume that substance gets trapped in his stomach, so it helps digest food faster because it will acidify it, which is either good or bad depending on who you ask.
Quirk weakness: Well, a suit usually does it best, it will attach to your haemoglobin so try and don't have that happen. Otherwise, high PH levels will hydrolyze the substance, that will help you. Higher oxygenized places will help destroy the substance as well.
Costume: (optional) Like that one guy with the gas mask in that one episode I forgot, I will expand upon this later.
Others: Hakuna Matata. I'm only 12% sure that his quirk can actually work in real life.