http://metanorn.net/2011/08/steinsgate-20#comment-80943
Yuugo doesn’t shoot Moeka. And back in ep19, a foreshadowing is also omitted. When Okabe returns to the lab after he has visited Moeka’s apartment, he notices there’s an electrostatic discharge on the 2nd floor, which means someone has used the phone microwave. But nobody is there when he arrives at the machine. As his Reading Steiner didn’t activite, he doesn’t give it a thought and timeleaps.
When confronted by Okabe and co in his house, Yuugo simply pulls out a pistol and asks if Moeka has betrayed them. He pretended to be a motherly figure because it’s an easier way to control Moeka. Okabe is pissed and reveals that Hashida Suzu, the one who raised Yuugo, was indeed Amane Suzuha, a time traveller who has dedicated her whole life fighting SERN. Yuugo is shocked as Okabe hasn’t talked about Suzu with him yet in this timeline. He claims that all Rounders are like cattles and will be “disposed of” once their mission is fulfilled. He then pulls the gun at his head saying that he’s sorry for failing Suzu. Okabe trys to stop him, but with a smile, he shoots himself. Moeka throws up. Okabe is raged at how Yuugo smiled committing suicide and being so cruel to abandon his little daughter. He retrieves his phone and says Yuugo has probably saved both Moeka and Nae from SERN by killing himself. He suddenly realizes that Nae might saw what has happened. He searches the house but can’t find her. The group then escapes to Moeka’s apartment.
In the apartment, Okabe phones Daru to prepare for a D-mail, but the tuning will take about 5 mins. As they are waiting, Kurisu recalls that she saw Nae running away when she was guarding outside the house. Suddenly Nae comes in the apartment and with a “Tutturu” greeting, she runs a knife through Moeka’s chest. Okabe and Kurisu are shocked and wonder if she’s being possessed. Nae says she has longed for the death of Moeka, and she will kill Okabe 15 years later. Then she runs off with a maniacing laugh. Okabe rushes to Moeka and she says she’s sorry for killing Mayuri. Okabe thinks that she’s referring to her other self in another timeline. He says he has already forgiven her, but Moeka just apologizes again and again and again in tears, until she passes away. Kurisu urges Okabe to send the D-mail, but he decides that he would never leave without the truth, thus timeleaping to the time before they confront Yuugo.
This time Okabe waits outside the house instead of Kurisu. He catches Nae when she escapes from the house soon after the gunshot. She says she will never forgive Okabe and Moeka for letting her father commit suicide. It is revealed that Nae has joined the Rounder in the future, and she hunted and tortured Okabe to death in 2025, then used the timeleap machine to jump 2738 times back to 2010 to kill Moeka. She stabs Okabe in his arm and pinches his wound, claiming that he should be regretted and tremble in fear for the rest of his life, that she will be back in 15 years to kill him. She runs off as Kurisu approaches. Kurisu checks Okabe’s wound and suggested that he should go to the hospital. He says it’s all his fault to make everyone suffers and he won’t let Nae has her revenge. Okabe then sends the D-mail.