Shounen Ga Otona Ni Natta Natsu Cap 1 2 3 - Sub New ~upd~

The narrative focuses on , a teenager who has lived with his older sister, Reiko , since their parents passed away in a car accident. While Reiko is a brilliant chemist who raised him, she often maintains a plain and unkempt appearance, leading Ryuuki to see her strictly as a maternal figure.

The series is available as both a manga and a four-episode produced by Queen Bee.

: Focuses on the deepening bond between Ryuuki and Kirill, including a notable "skinny dipping" scene at a river with his friends.