Transmigrating into Jujutsu Kaisen, but It's an Ultraman Meeting

While gazing at the stars in space with his human host, X, Ultralord, is swept into an unfamiliar universe by a temporal maelstrom. To make matters worse, he gets separated from his beloved Daiji.

Even worse, the terminal he's possessing lands face-first in a pit. The world is completely dark!

Good news: Three high schoolers with different-colored hair soon pick him up.

Bad news: They seem to have mistaken him for their teacher.

Great news: Their actual teacher shows up, bringing his Daiji with him!

Terrible news: He can't become one with Daiji anymore!

Daiji reassures him that he'll stay by his side no matter what, but X still secretly sends an Ultra Sign into space, hoping for help from a senior with relevant experience.

But the guys who show up don't seem very reliable...

The Energetic Three Plus One group:

Itadori: Huh? You want to live inside my body? But there's already a really scary resident in there...

Yuji: Don't worry. From now on, our three-person team has your back!

Who Even Is the Monkey group:

Naoya: If I've committed a crime, let the law punish me. Don't let a monkey teach me how to behave and keep burning me with its badge!

Little Bu: Awooo!

Nobody Backs Down group:

185: You think you can transform whenever you want? That'd make me look pathetic! No way!

Twenty Thousand Years: You don't get a choice! Glasses, fly!

Reliable Stand-In group:

Megumi: We agreed this was only temporary. Once you find your guardian, you'll leave my body.

Diamond Puppy: Okay, then could you ask your big bro to tell my big bro something nice about me? Sob.

Looking at the chaos all around him, X cries, "Why are there so many people here? There aren't even any monsters to fight!"

Gold Man: Hello.

Reader notes:

1. X and Daiji are the only couple.

2. The timeline and power levels are all over the place. Apologies for out-of-character portrayals and the jokes.

Theme: The bond of light