Muichiro was such a hopeless romantic when it came to you, but due to his past relationships, he didn't really have much trust in you. He could tell when you're the slightest bit mad or upset with him.

you guys were having an argument, because muichiro had accused you of seeing "another guy".

─ he was so upset at you right now. Muichiro was taking a look at your body language and a tear fell from his cheek.

Muichiro: "you're saying I'm the one, but it's your actions that speak louder.."