Moeka Kiryū (桐生萌郁, Kiryū Moeka) is a part-time editor whom Rintarou encounters in Akiba. Moeka is practically glued to her phone and cannot function without it. Even when face to face, she prefers to communicate by email.
She is searching for the legendary retro PC known as the IBN 5100.
Moeka is a tall, elegant, expressionless woman. Her physical attributes include pale toned skin, light nut-brown hair, pinky amber eyes and a tall, slender profile. She is usually seen with a purple phone and rectangular glasses. Her outfit consists of a white button up top with black arm cutouts, a black belt with a checkered buckle, a short black skirt, and black heels. Moeka is also the oldest among all the girl characters, being 20 years old, as well as being the tallest and also the bustiest.
Her Rounder uniform consist of a black jumpsuit, black big boots and a black belt. She also ties her hair to make it easier to move.
Personality wise, she is quiet, absent-minded, reserved, has difficulties interacting with people, and is seen to be expressionless most of the time without actually reacting towards anyone or anything, except for certain situations, her preferred form of communication is via text messages even if the person she is "talking" to is right in front of her. Therefore, she is very protective of her phone and becomes agitated if someone tries to take it from her hands. Moeka is never shown to interact with anyone properly, and her maturity has yet to be proportionate with her age, due to a certain turn of events in her past. Rather, Moeka is quite clumsy and the type of person that doesn't know how to take care of herself, as she often worries more about the dearest person for her rather than herself, fearing being abandoned.
Via mails, Moeka is a cheerful and carismatic person, contrasting highly with her real-life personality. As such, Moeka doesn't have confidence in herself personally, as she doesn't want (at first) to show herself to her mother figure, FB, saying she doesn't want FB to know the "real her".
Moeka's real personality, according to Rintarou in Hiyoku Renri no Darling, is that of a lonely little girl who desesperatly wants to be needed and loved by someone. As she never had anyone that cared about her, causing Moeka to think she's "unneeded". While Moeka is capable of carrying out atrocities for acceptance, she strives to be loved and has the potential to be a good person if led in the right direction. As said in Moeka's image song, "To be Loved".
In the Gamma worldline, Moeka can talk normally without using mails, though she says she's not good with conversations. She is very responsible, serious, incredibly perceptive and could even be called cold-hearted, since she easily killed, with Rintarou, two Europol agents. She apparently has more confidence on herself and isn't so much devoted to the person that saved her in this worldline. As such, Gamma's Moeka is much more independent in comparation with Moeka of others worldlines, though she constantly worries about Rintarou, as it was he that, according to her, gave her a reason to live, and saved her life various times.
In one of the drama CDs, Moeka narrates a message she sent and sounds like a completely different person.
As a Rounder, Moeka seems to be completely cold, calm and ruthless.
Moeka's childhood is a mystery, though it's implied in Darling of Loving Vows that her parents didn't want to have her and often said to Moeka that she's an unwanted child, constantly abusing her. It's speculated that or they abandoned her or died an unfortunate death. It's unknown what happened with Moeka after that, though she probaly didn't make bonds with anyone, due to that, Moeka fell into a deep depression for hating the world, and thinking she didn't had a reason to live, Moeka decided to kill herself. At that moment she received a mail from the enigmatic FB, changing her life forever. Seeing FB as the person that gave her life meaning, as FB often acted like a mother towards Moeka, speaking about Moeka's worries and stuff that troubled her, she devoted every waking moment to carrying out her given orders, developing a dependancy on FB and the mails provided.
Rintarou first encountered Moeka around the RadioKaikan building when he was revisiting the "satellite crash site". Moeka took a few pictures of him, which irritated him; She says that she didn't mean to take photos of him, but the location, to remember where she was. Moeka asks Rintarou if he knows anything about a phantom retro PC, named IBN5100. Rintarou says that he's Super Hacka might know something, then, Moeka ask Rintarous's email, in order to obtain Daru's information about the IBN5100; But Rintarou refuse, causing Moeka to chase him. After Rintarou notices her, Moeka shows his photo on her cellphone and says that in order to delete it, Rintarou has to exchange mails with her. Rintarou give up and send her a message. Moeka says that she will email him later. She was apparently a reporter for a magazine called Arc Rewrite, according to her introduction.
After a bunch of mails questioning about the IBN5100, Rintarou says that he successfully obtained it and Moeka visits his lab, asking to see the IBN5100 (as she was the one who suggested it to him). As Okabe ignore her mails, Moeka attempted to carry the computer away (before crumbling under the box's weight). Rintarou reluctantly dubs her "Lab Member 005" to prevent her from leaking the IBN's secret. She also requests to send a D-mail in order to prevent herself from buying a new phone.
When the Lab is about to end the Time Leap machine, Rintarou bumps into Moeka and she questions him about the nearly ended machine and what is a Time Leap. After Rintarou answer all of her questions, Moeka congratulates him.
After the Future Gadget Lab perfected the time-leaping mechanism, a team of Rounders, led by Moeka, storms the lab and holds its members at gunpoint. She ordered them to hand over the Time Leap Machine, Mayuri questions Moeka about being a lab mem, though this only causes Moeka to points her gun at her. Hesitating, Moeka shoots at Mayuri, causing Rintarou to panic. She points her gun at him and prepares to shoot, but Suzuha Amane rushed in and took out the whole Rounder squad, and entered a standoff with Moeka in quick succession, giving Rintarou his chance to time-leap back in time to prevent the attack.
Rintarou tracked her down and attempted to force her to abandon her assault, but was captured by her Rounders. The group then proceeds to breach into the lab to kills Mayuri and capture Kurisu and Itaru, again, prompting Rintarou to leap into the past.
Mayuri continues dying ether shot by Moeka or other reasons such as heart attack, hit by a train and shot by other Rounders.
As Rintarou discover that to stop Mayuri death he has to cancel every D-Mail sent, he visited her house to revert her D-mail and convince her to cancel the attack, only to find police officers around her apartment; she had hanged herself. He time-leaped again, and returned to her house at night. Moeka seemed catatonic, mumbling to herself while typing uncontrollably. Rintarou attempted to wrest the phone from her hand, causing her to violently revolt. He successfully sent a D-mail to the past, but nothing changes (as the phone Moeka convinced her past self to change did not appear). After pinning her to the ground, telling Moeka both about her imminent death and FB had most likely betrayed her, she told Rintarou the story of FB and how they became a mother figure for her. Rintarou also figured out that Moeka actually D-mailed herself the location of the IBN.
Realizing that a D-mail from FB's phone could cancel Moeka's, Rintarou decided to hunt for FB by staking out the IBN drop-off point. After Moeka joined the stakeout, the two pursued the IBN and witnessed it being passed along by different people, one such person being Rintatou's landlord, Yuugo Tennouji. The two visited Yuugo while Kurisu waits outside his house. While Rintarou confronted Yuugo about his secret identity, he called Moeka "M4" a codename that FB had given her. Pulling a gun on Moeka, Yuugo admitted that he was FB, pretending to be a woman to appeal to Moeka's insecurity; he also informs the two that Rounders who locate an IBN 5100 are slated for death. Yuugo instead proceeds to kill himself to, much to Moeka and Rintarou's despair.
In retrospect, Rintarou believed that Yuugo cared about Moeka's well-being, and spared her life in a last-resort effort to protect her. Unfortunately, Moeka's death in that world-line was guaranteed, but this time around, it was Nae who killed Moeka; Nae then warned Rintarou that she will kill him in 2025.
As Moeka dies, she apologized to Rintarou for Mayuri's death, believing that her death is her punishment for killing Mayuri in another world-line; And that Rintarou is right to hate her, as she would kill to protect the place she belongs. (FB's care for her) Reminding himself that Moeka did not kill Mayuri in this timeline, Rintarou forgives Moeka as she dies, then sends the cancellation D-mail (unless the player decides to wait it out, in which case Rintarou time-leaps so he can interrogate Nae about his death in 2025).
Moeka is not seen or heard of anymore after her death in the Alpha worldline.
After 1% divergence was reached (true ending), Nae injured herself and Moeka helped her with a first aid, bringing her to Yuugo's story, due to that, Nae introduced Moeka to Mr. Braun and he decides to give her a job. After Okabe got released from the hospital, he gives Moeka the lab's pin, saying that it's the proof that she is the Lab Mem 005 and that she can come to the lab whenever she wants. Moeka smiles and thanks Okabe as he goes to the lab.
- "Look, even if we were enemies in the world you were before, right now I'm your ally. Even if the whole world turned against you, I would continue to be your ally." -Moeka to Okabe in Gamma worldline.
- "The "me" that you are talking about is also a different me, now I only want to help you." -Moeka to Okabe when he accused her of betraying him.
- "Did I do something wrong? I'll fix it, I promise. Just don't abandon me. I'll do anything for you, FB!" -Moeka desperate when FB stopped sending mails to her and replying to her mails.
- "I was always told that I am an unwanted child... over and over... that's why I truly believed that I wasn't needed!" -Moeka to Okabe in Hiyoku Renri no Darling.
- "I had nothing except FB... The only place I belonged... I would do anything to protect it... you're right to hate me..." -Moeka to Okabe
- "I killed... someone... precious... to you... so this... is my punishment... I'm sorry..." -Moeka's last words.
- Moeka doesn't know how to cook, clean, and how to do other domestic labors as shown in Steins;Gate Hiyoku Renri no Darling. She only eat instant foods and almost never clean her apartment.
- Moeka can apparently type and send SMS's at the speed of normal speech, which leads to Rintarou calling her "Shining Finger".
- The nickname "Shining Finger" is the ultimate attack of Shining Gundam in G Gundam.
- Originally, the creators had a Moeka route in mind but in order for the player to feel closer to the protagonist, Moeka was made to be a character the players would feel antagonism against, so they dropped the Moeka's route idea.
- Moeka can kill anyone if she's ordered to, though she hesitated when she killed Mayuri.
- The Drama CD, Steins;Gate Gamma Hyde of the Dark Dimension, is considered by fans to be her route that never existed within the Visual Novel.
- In Steins;Gate Hiyoku Renri no Darling, Moeka writes a novel called "My Rainbow". The story is about a girl who is traumatized about not having a reason to live and not being needed by anyone, but she meets a boy at her part-time job that changes her life. Little by little, she starts realizing that she is important and starts to live a brighter life.
- Lab Mem 005, joined at episode 6. Moeka joined because she wanted to use the IBN5100.