Ouma was waiting for Kiibo to die.
Now, hear him out- Ouma didn't actually want Kiibo to die, but it was the only way for them to meet again. After Ouma was crushed by the hydraulic press he was awoken and revived, but as a ghost. Pretty cool, right? He had the chance to apologize to everyone else who was dead, he got to apologize to Gonta, and he got to apologize to Kaito. And he was hoping to apologize to Kiibo- when he died, of course.
Most of the other dead students were aware of Ouma's motives before he died, so they forgave him- well, most of them did, Kaede, Gonta, and Amami were some of the few who accepted him. The others weren't as accepting as they were, like Iruma, she had really only talked to him once since they died, where her only words were "You lying little abortion!" to which he said "Whatever, you useless bitch!" And then Kaede split them up. Then there was Korekiyo, who Ouma wouldn't even go near him. If he wasn't creepy before, he was pretty deformed from the 'purification' Monokuma performed on him, so Ouma didn't really want to bother him. Then there was Kaito- who had more of less forgiven him, that's what Ouma thought, at least.
But that didn't matter, Ouma was waiting for Kiibo. And he would wait, and wait, and wait until Kiibo joined him.
So when Kiibo saved Saihara, Himiko, and Maki. Ouma felt happy, as happy as he could be watching his favourite robot die in an explosion. He felt pride, Kiibo did this to save his classmates, he did this to protect them. It gave Ouma hope, and it gave him even more hope when he realised that Kiibo would be joining him soon.
So once again, he waited.
It only took Ouma about an hour to 'transition' into a ghost, so after about two hours of waiting, Ouma got worried, Kiibo should've been here by now! Ouma was growing impatient, but Kaede told him not to get too worked up about it, he'll be here soon. But he couldn't help but doubt her.
After one full day of waiting, Ouma started to lose hope.
Maybe Kiibo had bypassed the ghost stage and gone straight to heaven? Robot heaven? Ouma hoped so, Kiibo deserved it, he deserved the best (Even if he wouldn't admit it out loud). After the three weeks that Ouma knew Kiibo, he developed a little crush on the robot. It took him a while to notice that he actually like-liked Kiibo, he really wanted to tell him, but what if Kiibo rejected him? Ouma couldn't stand the thought of it.
So he pretended to like Saihara. Despite the fact it was painfully obvious he was lying. At least it covered up Ouma's crush. But, apparently it wasn't good enough considering as soon as he met ghost-Kaede she asked him why he didn't just confess to Kiibo. Ouma didn't know how to respond to that, so he just made up some lie and left it at that.
After the fifth day of waiting, Ouma went to Korekiyo.
"Hey, Shinguuji-Chan" Korekiyo glared at Ouma, but greeted him with a wave "Uh. I was just wondering- you know allll~ about fairytales and ghosts and shit, right?" Korekiyo simply nodded, he didn't talk much anymore "So~ When do you think Kiiboy will... y'know, become a ghost?" Korekiyo thought for a moment, before opening his mouth and speaking up;
"Perhaps he wont?"
That was the first words he'd heard from Korekiyo since he died, his voice was slightly garbled and sounded stressed, but it wasn't the sound of his voice which worried Ouma, it was the content. Ouma growled lightly "What do you mean? Of course he will- we did!"
The other took a deep breath "Kiibo-kun is not truly human, is he? If he's not human, then he won't become a spirit" Ouma opened his mouth before closing it again, then opening it and closing it again "Now, if you'll excuse me Ouma-Kun, I must be off"
And away the disfigured spirit went. He seemed quite pissed, honestly. And Ouma was glad he left, but he couldn't get over his words. What if Kiibo didn't come back? But Amami, Kaede, Hoshi, Toujo, Angie, Tenko, Korekiyo, Iruma, Gonta, Ouma, then Kaito came back! They all returned as ghosts, their souls bound to the Killing Games. That's what Kaede believed was tying them to the Earth, their souls.
Then it occurred to Ouma- a small, tiny, thought passed through his head, it only stayed for a few seconds but it resonated within him for hours. Ouma was stronger than this, he had to be, he was the SHSL Supreme Leader. One little thought couldn't cripple him like this one did. But what was this thought?
Do robots have souls? After all, they are just extensions of computers, Kiibo was artificial, and so was his life. He didn't have a soul, so did that mean he was dead forever?
...
Ouma decided that he would wait, just a little bit longer.
