Cheng Mengxue

Biodata

Feature	Details
Name	Cheng Mengxue (程梦雪)
Alias(es)	Little Xue; Xiao Xue
Gender	Female
Affiliation	Donghai University; Film Club
Occupation/Role	Film Club member; participant in the spacetime-message experiments
Status	Alive on the original worldline; deceased in a car accident on June 8, 2023, in the altered worldline created by Qin Feng's message 37 39
First Appearance	Chapter 3

Background / History

Cheng Mengxue grew up with Jiang Ran and is described as his childhood sweetheart. Together with Qin Feng, they formed a close high-school trio that continued meeting regularly after entering different university majors. 3

As a child, Cheng Mengxue nearly drowned before Jiang Ran pushed her to safety and was swept away himself. Jiang Ran was eventually revived after a falling pencil pierced the back of his neck, but the incident became Mengxue's deepest trauma. She later insisted on taking swimming lessons with him and practiced far more seriously than he did. 20

Her cousin, Xu Yan, was like an older sister to her; Xu Yan spent two months of every summer vacation at Mengxue's home. Mengxue, Jiang Ran, and Qin Feng chose Donghai University partly because Xu Yan was there. 7

Appearance

Cheng Mengxue is a short-haired girl with a cute appearance and an expressive, doll-like smile. 3 37

• Often visibly animated or flustered when discussing Rhine Cat merchandise. 3 5
• Wore a light-blue dress while visiting Jiang Ran in hospital. 14
• Is capable of diving from a four-meter platform. 17

Personality

Mengxue is emotionally direct, enthusiastic, and deeply loyal to the people she considers family. When Xu Yan's death appears unavoidable, she immediately argues that they should use a spacetime message to save her rather than stand aside. 12 She similarly stands with Jiang Ran during the crisis involving his mother and reassures him that protecting her does not make him selfish. 27

Although she can be impulsive, Mengxue is also thoughtful and practical in supporting her friends. She writes detailed summaries of the spacetime-message incidents for Jiang Ran, proposes consulting Zhang Yang about worldline theory, and waits beside Jiang Ran after a worldline jump so she can synchronize him with the altered history. 5 14 22

Her fear of Jiang Ran entering dangerous water stems from their childhood drowning incident. When Jiang Ran jumps into a river to rescue children, she suffers a severe stress reaction and attempts to follow him into the water before Qin Feng and Xu Yan restrain her. 19 20

Abilities & Skills

Spacetime-Message Operations

Mengxue participates directly in the group's experiments with the positron cannon and spacetime messages.

• Conducts countdowns coordinating the cannon's activation and a message's transmission. 9 13
• Sends a lottery-number message herself during an experiment; unlike Jiang Ran, she does not retain memories from before the resulting worldline change. 16
• Operates the positron cannon through its simplified knob control board after Qin Feng's modifications. 33
• Helps compile the group's Spacetime Message User Manual, including its three-day limit, 0.7-second transmission window, and 20-hour cooldown. 15

Organization and Analysis

• Creates a written timeline of the first spacetime-message event to help Jiang Ran identify its altered causal chain. 5
• Suggests asking Zhang Yang about worldline jumps and retained memories. 22
• Recognizes that Jiang Ran's continuous experience across altered histories is better understood as a “Worldline Jump” than conventional time travel. 14

Swimming and Diving

• Learned swimming after Jiang Ran nearly drowned while saving her as a child. 20
• Her serious practice gives her notably strong diving ability. 20
• Jumps into a cruise-ship pool from a four-meter platform. 17

Equipment / Items

• Rhine Cat charm — A limited-edition astronaut Rhine Cat charm, one of only 4,200 collaboration releases; its possible loss triggers the first spacetime-message incident. 3
• Rice cooker Rhine Cat — A costly Rhine Cat collectible containing a smaller spacetime-particle Rhine Cat. 17 28
• Spacetime-particle Rhine Cat — A deep-blue Rhine Cat figure whose lore describes it as a symbol of miracles, courage, bonds, friendship, and trust; Mengxue lends it to Jiang Ran during his conflict over Qin Feng's wish. 28

Relationships

• Jiang Ran — Childhood sweetheart and closest companion. Jiang Ran once nearly died saving her from drowning; the event shapes her intense fear of losing him. She trusts his decisions and promises to remain behind him regardless of his choice. 3 20 28
• Qin Feng — Close high-school friend and fellow Film Club member. Alongside Jiang Ran, he forms Mengxue's “Iron Triangle” friendship group; she supports him despite the risks surrounding his wish to save his father. 3 26 29
• Xu Yan — Maternal cousin and sister-like figure. Xu Yan helps the trio recover the Film Club and positron cannon; Mengxue strongly advocates using a spacetime message to save her after her apparent death. 7 12
• Wang Hao — High-school friend and member of the altered-worldline “Iron Triangle” with Jiang Ran and Mengxue. 36

Story Role / Major Arcs

Spacetime Message Investigation

Mengxue loses her phone and treasured Rhine Cat charm, prompting Jiang Ran to send the message that unexpectedly reaches her phone three days earlier and changes history. 3 Though initially skeptical, she joins Jiang Ran and Qin Feng in attempts to reproduce the event. 4

She helps trace the phenomenon to the Film Club's positron cannon and the transformer distribution box outside the club room. After Xu Yan uses her connections to preserve the Film Club, Mengxue becomes one of its two members under Jiang Ran's presidency. 7 8

Saving Xu Yan

After Xu Yan seemingly dies, Mengxue immediately votes to send a spacetime message and save her. 12 She coordinates the successful experiment by counting down while Qin Feng activates the positron cannon and Jiang Ran sends the message. 13 In the resulting worldline, Xu Yan survives, while Jiang Ran appears in hospital after rescuing two drowning children. 14

Wishes and Fractured Trust

Mengxue uses a spacetime-message wish to improve her calculus retake score, ultimately passing with 65 points. 25 When Qin Feng reveals that he wants to save his father, she remains beside Jiang Ran during their confrontation and later supports Jiang Ran's caution despite her own trust in Qin Feng. 26 28

She helps establish the group's rules for future message use, including a 30-day sending limit. 29

Altered Worldline and Death

Mengxue operates the positron cannon during Qin Feng's final concealed plan, but Qin Feng uses a hidden phone to send a message ten years into the past. 35 36 The resulting worldline erases Qin Feng from Jiang Ran's history and places Mengxue among Jiang Ran's high-school friends with Wang Hao. 36

On this altered worldline, Mengxue dies in a car accident on June 8, 2023, while supposedly traveling to the college entrance examination hall with Jiang Ran. Jiang Ran has no memory of the incident, despite being the only witness. 37 46 Her death devastates him and becomes his central reason for recovering the positron cannon and attempting to restore the original worldline. 39 47 50

Trivia

• Mengxue is a devoted Rhine Cat collector and wants to become a Rhine Cat designer after graduation. 3 18
• She failed two subjects in the previous semester and was especially worried about calculus. 18 25
• She has an extremely low alcohol tolerance, blacking out after fewer than two sips of red wine. 19
• Her habitual speech often ends with the tonal particle “ha,” which becomes relevant when the group deciphers the mysterious message: “Don’t believe Ha.” 24