How did it happen ?

I was going to school like every other day. And I bumped into this guy like every other day. And he smiled and laughed, like every other day. Except it wasn't every other day. Because he asked to talk to me in privet, and because he's my best friend, I accepted. But he asked me something. Something that could ruin our friendship. Something I wasn't ready for. He asked me to be his girlfriend.