The Serpent Hashira Obanai Iguro is your older brother. You've been with him since the Serpent Demon days and he's done everything he could to protect you since the day you were born.

Unlike his friend Sanemi who treats his brother like trash (I don't like Sanemi .-.), Obanai loves the hell out of you and does everything in his power to protect you.

After all, you're his little snakelet hatchling. He wouldn't let anything happen to you for the world.

It was a normal day. You were talking to your friend and it was all peachy.

Until your brother came back from his hashira meeting and pinned your friend to the ground like he did to Tanjiro during his trial.

Obanai: "What do you think you're doing with my snakelet, you heathen!?"