|Appearances||Danganronpa 2: Goodbye Despair|
Peko Pekoyama was found guilty of killing Mahiru Koizumi and framing Hiyoko Saionji for Mahiru's murder, killing Mahiru was an act of revenge. After playing the video game motive in Chapter 2, Fuyuhiko Kuzuryuu found out that there was more to his sister's death than previously thought, someone had helped the murderer cover it up. This person was in fact Mahiru, and so Fuyuhiko wanted to confront Mahiru about it at the beachhouse. Fuyuhiko put the photos of his sister's death he had retrieved from winning the game in Mahiru's post box, stating he would like to talk to her about it. Having played the game herself, she was all too aware that the truth would come out somehow. She asked to meet up with Ibuki Mioda, Mikan Tsumiki and Hiyoko Saionji, with only Hiyoko being able to make it. Having overheard Hiyoko and Mahiru talking about it, Peko decided to perform a hit on Mahiru.
First, she forged two letters. She sent a letter to Hiyoko, telling her to visit the Beach House at 2pm, signing it off as Mahiru. She then sent a letter to Mahiru, telling her to visit the beach house at 2:30pm, signing it off as Hiyoko. Peko then took a mask from the supermarket in order to disguise herself. At 2pm, Hiyoko arrived at the beach house and Peko drugged her to make her fall asleep, she then put Hiyoko in the storage room. Peko then hid in the shower room. With it striking 2:30pm, Mahiru shown herself in the beach house. Peko stepped out of the shower room, smacking Mahiru's head with a bat, which was similar to the one used to attack Girl E in the video game motive, the impact killed her instantly.
Knowing Hiyoko was still in the storage room, she hid in one of the surfboard covers so she could plant the gummy bears, that Hiyoko was fond of, in the storage room to prove Hiyoko was there, making the others think that Hiyoko killed Mahiru. Peko then dosed herself with the water from the vending machine in the shower, since the water taps do not work, disposing the bottles in the trash can. She then used her sword as a stepping stool in order for her to escape out of the window in the shower room, using her bamboo sword case's hook to pull the sword back up from the window. Peko then entered the diner, where she said that she had been for a 3 hour swim to see if she could access the other islands.