It doesn't make sense at first on why Domon thinks that he is still in the year 3000, it was then revealed that it is because of datamentia, which is basically the after effects of cramming too much 20th century data and your brain not handling properly. So yeah, Domon was sent to the hospital after fainting due to too his brain not being able to handle too much 20th century data. At the hospital, we see Domon's dream of his life back in the year 3000. His life as a fighter and even see the glimpse on how mixed combat is like in the future and I got to be honest, it might give 21st century MMA a run for its money when it comes to blood and violence. I mean, seriously, bladed weapons are legal?!
Thankfully, Tatsuya and co. managed to save Domon before the quack surgeon can cut his body, which led us to another episode of his datamentia. Because that plot with the quack surgeon feels like it is something they kinda glossed over in this episode, I'll just focus on Domon's issue in this episode. If there is one thing this episode made me realize is that the less we see the year 3000 in this show, the better this show gets.
For Domon, the year 3000 is not a year, but his home and he misses it. Earlier in the episode, we see Tatsuya ignore Domon being all nostalgic for the future because for him at that time, the year 3000 is just 1000 years in the future and around that time period, he's dead and no one knows him. In Domon's case, the year 3000 is essentially moving from a country to a different country. Just substitute the years with countries and you can pretty much sum up Domon's dilemma. He's a guy who just moved to a new country for work reasons and he misses his home. Or in Domon's case, time period.
The episode ends thanks to Tatsuya babbling about what happened to Domon, Domon gets teased by his teammates because for a big guy like him, he is the first person who got to experience this kind of home sickness. It's funny at first but when you think about it, did the rest of the team experience home sickness in public or did they managed to hide it in front of their teammates because their current mission to stop the Londarz family?