Su Xiaoman, an IT girl who appears to be well-behaved, is actually a good girl in the eyes of her parents and an ordinary programmer in the company, but in the online game "Second Dimension Online Game" she transforms into the invincible red-clad swordsman "Red Sleeve Sword". An accident made her become an online writer, and she met the mysterious doctor player "Bai Zhi" in the game. When she discovers that the other person is actually Xu Mo, a divorced medical professor with a child, she sticks to her principles and chooses to distance herself. However, they meet again because of Xu Mo's autistic daughter, Xiao Yu.
