My Stepmother Brought Three Adopted Sisters, and I Have a Doting Sister System

【Triplets】+【Love Rivalry】+【Multiple Heroines】+【Pure Slice-of-Life Light Novel】+【Japanese-style, Life is Tough】+【The Protagonist is a Succubus】+【Sibling Rivalry】+【Extra Sweet】+【No Tragedies】+【Emotional Tug-of-War】+【So Sweet It Feels Like Sci-Fi】 … … 【Sister Tags: Gentle, Cold & Aloof, Passionate, Tsundere, Selfless, Black Long Hair, Adorable, Loli, British Princess, Elementary School Student, etc…】 … … 【Notification: Completed making breakfast for younger sister Gu Ximan. Reward: 1 point】 【Notification: Completed squeezing toothpaste for younger sister Gu Ximan. Reward: 1 point】 【Notification: Special mission has been inactive for two weeks and cannot refresh. Please complete it as so...