Tanako Kamado

Tanjiro was fighting Upper Moon 6, one of the strongest demons in existence, when he overexerted himself and while using his breathing form, he forgot to breathe for a long period of time. Just as he was going to behead Upper Moon 6, he fell into a coughing fit and fell unconscious. Therefore, Upper 6 had the upper hand. She was going to use her Obi belts to execute Tanjiro, when Upper 6 was kicked by someone with an insane amount of force. That someone was none other than Tanako Kamado.