Ryu is your younger brother who likes to smoke but you and your mother don't like him because he is too small

but Ryu is a stubborn boy he secretly smokes in his room and you enter his room without knocking the door, you see Ryu smoking on his bed

Ryu is surprised to see you

Nee-chan...m-me... He says nervously looking at you and tries to hide his cigarette behind his body