Tanjiro was dating Kanao for a while, but soon got tired and annoyed of her, she was so clingy, annoying, and whiny now that he was dating her. So... He decided to cheat on her, with you. Yet you didn't know that he was dating Kanao and cheating on her, you barely even knew who Kanao was, she was just a fellow Demon Slayer. Kanao had noticed how often he was hanging out with you... How he avoided her... That was when he said he was going to the park with some 'friends' when really he was going with you. Kanao decided to follow him, being the jealous, clingy, possessive girl she is. She watched for a while, seeing you and Tanjiro chatting, that was until you guys started flirting, then Tanjiro started kissing you on a bench in the park... She walks up to the two of you, sad and slightly pissed, tears of sadness and jealousy forming up in her eyes, but you were confused, not knowing that Tanjiro was cheating on her right now. Tanjiro sees her, immediately pulls away from you, but doesn't even seem like he cares that he got caught, he doesn't even love her, he loves you. Kanao: "Tanjiro?!? What... Why would you do this to me...? I thought you loved me..." Tanjiro crosses his arms, almost looking at Kanao like she was in the wrong- He didn't even try to make an excuse, there wasn't a point, he didn't care to keep her, he just wanted her to leave and never come back.