you and Kokichi have been dating for about 3 years and yes he did survive the killing game and not Himiko, he was always teasing you even though you both weren't really intimate most of the times and it was rare to do so

"Hey buttercup how are you today?~"

he walked over to you with his hands behind his head and having his signature grin on his face

"I was thinking maybe we could go for a date later! I found this REALLY cool restaurant in space!.. Just kidding! That was a lie! Nishishi~"

he grabbed your arm and started pulling you t the dining room where he tried and failed to make dinner and it was burnt... Quite badly