Li Tianxi is depicted with naturally pink hair and eyes. In the present timeline, she wears her hair in long pigtails with straight bangs framing her face. Her school uniform consists of a lilac-blue blazer worn over a yellow vest and a light pink button-up shirt, accented with a matching lilac bow. She pairs this with a short lilac-blue skirt, long white socks, and gray dress shoes.

In childhood flashbacks, her pigtails are shown to be shorter, and she is seen wearing a brown dress decorated with white polka dots.

Li Tianxi is portrayed as a gentle yet emotionally fragile girl, shaped by her traumatic upbringing and her complicated relationship with her twin brother, Li Tianchen. Despite fearing him and recognizing the immorality of his actions, she continues to show concern for his well-being, reflecting both her compassion and conflicted loyalty. Although her mental state is closer to that of a child, she is capable of discerning right from wrong and understands the severity of her brother’s crimes.

Tianxi is highly sensitive and easily intimidated, particularly by raised voices or confrontations, a tendency stemming from her troubled past. Her muteness further complicates her ability to communicate her feelings, as her speech is often slurred and difficult to understand. Nevertheless, those close to her can generally interpret her words, and she is able to connect through alternative means of expression, such as responding to Qiao Ling’s stories conveyed through drawings.

Possession Through Photos
Li Tianxi possesses the ability to enter another person’s body through a photograph of them. While using this power, she is able to see what the subject is currently experiencing and gains access to their memories. However, she cannot directly control their actions and is limited to spectating. In addition, she feels the subject’s physical sensations and emotional state as though they were her own.

Her ability can also be combined with Li Tianchen’s power. When Tianxi is observing someone through a photo, Tianchen can manipulate her ability to indirectly take control of the subject in the present. During this process, Tianxi falls into a trance like state and remains unaware of his actions, though it is implied she may occasionally perceive fragments of what he does on her behalf.

Li Tianchen
Li Tianxi shares a deep and complicated relationship with her twin brother, Li Tianchen. In their early years, Tianchen was protective of his sister, going so far as to learn sign language in order to help her communicate despite her disability. The two shared a strong bond rooted in mutual care and reliance.

Following the traumatic events of their past, however, Tianchen became increasingly cruel and unstable. He committed multiple murders, often exploiting Tianxi’s ability to manipulate the consciousness of others in the process. Although Tianxi disapproves of his actions, she continues to care for him, reflecting her conflicted loyalty. Tianchen’s alliance with Qian Jin further entangled Tianxi in dangerous schemes, as he sought to use Cheng Xiaoshi’s time-traveling power to alter their circumstances. Instead, these efforts left Tianxi even more harmed and vulnerable.

Qian Jin
After the deaths of her parents, Tianxi and her brother were taken in by Qian Jin. Under his influence, Tianchen became his accomplice in carrying out assassinations, while Tianxi was unknowingly drawn into the killings through the use of her powers. Eventually, after her involvement in the murder of Chen Bin, Tianxi broke away from Qian Jin’s control. She later aided Cheng Xiaoshi, Lu Guang, and Qiao Ling in opposing his plans, an act that Qian Jin viewed as a betrayal.

Li Tianxi’s surname, 李 (Lǐ), is one of the most common family names in China. Her given name, 天希 (Tiānxī), is composed of tiān (天), meaning “heaven” or “sky,” and xī (希), meaning “hope” or “rare.” Together, her name can be interpreted as “heavenly hope” or “rare hope from the heavens,” which may reflect her symbolic role in the narrative as a figure of innocence caught within tragedy.