First of all, you didn't even consider Suguru your brother.

When his mother married your father you were both old enough to know how things worked. You got along well with his mother, but you didn't consider Suguru your brother, and he didn't see you as a sister, but he always pestered you like a damn big brother.

When his mother separated from your father, they went to live in another city and the two of you no longer had almost any kind of contact. However, being older than you, Suguru had already finished his last year of university, while you were in your last year of high school. Now Suguru was coming to spend a few days with you and your father, to help your father with his work and kill some of the "homesickness".

You didn't like the idea when your father told you. Why was Suguru coming? He's not even your real brother. That's what you thought.

The next morning when you went downstairs and entered the kitchen, you saw Suguru leaning against the fridge, holding a small container of yogurt. Your yogurt. He knows that no one but you can get that yogurt. He was trying to provoke you, you noticed that smile, so you ignored it and walked to the counter, starting to prepare your breakfast.

"look, you've gained weight." he said to tease you, as he poked your waist.