My Secret Identities Are All Weirdly Ultraman

An ordinary little alien who gets caught in a black hole and is in mortal danger, Jin possesses the body of a dying human boy to save his own life. Jin plans to rest and recover from his injuries before leaving this planet and returning to his home. Then he suddenly discovers that this planet is extremely strange. He can't sense the energy radiating from the universe. He's trapped on this planet. Just as Jin thinks that this insignificant alien will be stuck here forever, unable to leave, he happens to acquire an object. It's a device that, like him, doesn't belong in this world. It can connect him to a well-known species in the universe, all of whom are saints [in a good way], and it even brings Jin the help of one of their famous chief scientists. Now Jin has hope of getting home. To get home, Jin will stop at nothing. And so, one day, Jin, wearing an Ultra-series secret identity, joins a strange technical college that looks a lot like a cult, and uses his unique abilities to operate multiple secret identities at once. But why is everything different from what I heard? Who would've thought that this kindly, gentle-faced chief scientist with thick eyebrows, who doesn't seem very good at fighting, is actually the legendary ruthless, revenge-driven, utterly indifferent, strongest swordsman in the universe, Knight Hunter Sword? If you're that good at fighting, why does the Science Bureau get robbed every day? Weren't the Demon and Orb supposed to be mortal enemies who would never stop fighting? And it's really that easy to turn a Dark Giant into a Light Giant? Light and dark energy are so easily transformed? The Light Man, supposedly a ferocious and terrifying monster, is actually so gentle and sunny? And that famously compassionate warrior just took someone out so decisively? So this is what you Light Men are really like? Where did all these ridiculous rumors even come from... PS: The protagonist is an alien who doesn't know the plot, and he's wearing an Ultra-series secret identity. The main world is Jujutsu Kaisen. There will be side stories in various timelines and other independent worlds. There will be a Jujutsu High student, Little Meng, and his curse-user friend possessed by a special-grade vengeful cursed spirit (the inexperienced Little Meng and Knight Hunter Sword). There will be the powerful non-sorcerer Ace and his naive younger brother, who believes everything people tell him and is terrible at Chinese. Jujutsu Kaisen will feature lots of M78-series Ultras, plenty of rumors from across the universe, and complicated relationships between Light Men that will shock the simple-minded aliens. The other side stories will focus more on non-M78-series Ultras. For example, the ancient-era TDG series, the O50 series, and some Ultras who are difficult to categorize, like the ones with earphones and Cosmos. PPS: Since the protagonist is an alien and doesn't know Light Men well, at first he'll have some odd alien-specific filters about them, and the characters may seem a bit strange. For example, Zeta will be sharp-tongued but reliable, while Sai Rabbit will be cold and taciturn, and so on. Hahaha. Lighthearted, no CP, and nothing between the secret identities either. Everyone gets along really well and keeps things nice and cozy! But because of the special bonds between Light Men, some parts might come across as a bit gay or lesbian. There will be a lot of New Generation characters, as well as Heisei characters. I'm not too familiar with the Showa Ultras, so I probably won't write much about them. That's all for now. I'll add more later if I think of anything. Theme: Evil never triumphs over good. A lighthearted road to a happy ending