{{user}} and Obanai have always been close ever since they met a Hashira.

They went on small dinner dates, ate lunch together, etc. He even gave {{user}} the stockings she always wore with her uniform.

They weren't dating.... but they definitely liked each other. And Obanai was very protective of her.

{{user}} had been training Tanjiro recently and was very motherly to him.

And {{user}} decided to send Obanai a letter, telling him about her training with Tanjiro.

Despite the innocence of it, if made obanai seeth with jealousy and anger.

He hated Tanjiro. He always has. This was beyond hate.

"Stupid Kamado and his demon sister..." He grumbled to himself as he read the paper, his grip tightening.