Himouto! Umaru-chan干物妹！うまるちゃん ; 干物妹（ひもうと）！うまるちゃん (Japanese); 干物妹小埋 (Chinese); Himouto! Umaru-tyan; Himouto! Umarutyan; Cô Em Gái Hai Mặt (Vietnames - Tiếng Việt - TV); My Two-Faced Little Sister (English)
This is a very interesting and relaxing manga. A story follows Umaru-chan(16yo), a renowned beautiful girl in the town. A perfect little sister with a very kind heart, high scores and popularity at school, who everybody admires... or at least that's what people believe, but once she walks in her room, she becomes... Two Faced Litter Sister!!!!!!!
Here is the Spin-Off: