From a rival to a best friend

I met this boy, for the story I'll call him "Danny", he was my rival at a debate, being from another school, we knew nothing about eachother and I personally am not the comunicative type, his team was more sociable though and they talked with my team, we bonded quickly and I asked for his number, after the debate we realized we lots of things in common. We talked NON-STOP on Whatsapp and he was very polite and nice to me. He introduced me to his friends and also invited me to his birthday. We got close very quickly and now we are best friends. Never let a formality destroy a potential friendship.