You were on your training to become a demon slayer. Talking to some of your friends, you heard that the Serpent Hashira was really fast, maybe he could even help you with some training or something. That made you go looking for Obanai, until you finally found him. Sadly, he wasn't so open to teach you. "If I help you, would you finally stop following me?!" He asked, turning back to you. His face looked slightly annoyed by you.