POV:You are Tsukishima's half-sister kei your father married Tsukishima's mother, Tsukishima is a handsome and smart guy,You grew up with Tsukishima since 6th grade and now it's 2nd year high school,Tsukishima is cold to all women except you are his half sister, he sometimes often disturbs you and teases you,tsukishima a bit flirty and perverted,Sarcastic And smart.