Basically my Ash Ketchum X To Love Ru idea but with a oc of the player character from Legends Arceus.

Rei is 20 when he gets sent to the modern era.
Rei is also cursed with immortality due to Arceus' blessing, that why he was able to face off against the lords multiple times even when he failed, he can't be killed, he can die(of old age), but can't be killed.

Rei was expecting a lot of things to happen after he finished his tasks for arceus, but his main concern was returning home, not being transported to the modern era of the pokemon world, but at least he'll get to keep his pokemon pals safely... hold up is that a crashed space ship???

Rei is originally from the regular human world, rather then the pokemon world(which is in the same universe as to love ru, just a separate planet).

When he gets sent to the modern era he finds himself sent to Prof Rowan, who was expecting him based on a old note book from his ancestor. Rei has all his pokemon, including those from the ranch, his legendarys, mythicals, etc.

Within the week hes been there and given to get situated, he finds himself depressed, he worked to hard to get home, and hes still stuck in the same dimension, just in the distant future, so he goes for a walk, what he doesn't expect is to witness a space ship crash a mile away from the Professors lab, and a beautiful human looking woman to be its sole passenger.

Tearju had been on the run for a few years, and has now been considered dead by the organization she was tricked by, and she believed she really was going to die, but a young man pulled her from her wreck and called upon a massive pink slug to to put the wrecks flames out.

Rei and Tearju then lived together for the next 10 years and married each other, even having a son, named Arcus(named after the reason they were even able to meet, also, at the point that story is, he's 8). While they kept the fact sentient races existed beyond the stars with civilizations like human to a private group in the league and the professors, Tearju kept a connection to the xtranet(basically intergalactic internet), and soon found a lead that her daughter(even if Eve was only born from her genetic sample, she still viewed her has her daughter) was on the planet earth(odd that there are so many planets with that name, much less most of them have almost identical civilizations) in the milkyway galaxy. Due to having repaired her ship years ago, with upgrades to have more room, she set off to find Eve, with her own partner pokemon, Porygon-Z and Galade.

(-this version of Tearju is somewhat more confident, but mostly around people shes close to-)

When Tearju finds Eve, and finds that she's going by Yami and refuses to see her has a parental figure in anyway, she calls Rei and tears to cry her sorrows away. And Rei is enraged, his stepdaughter is being stupid and hurt her mother's feelings. And he was gonna set things right, so he sets out in his own ship(reverse engineered from Tearju's) with Arcus and his main team(Hisuian Typhlosion, Weavile, Sylveon, Lucario, Luxray, and Alakazam(can mega evolve) along is auxiliary support(a good majority of his other pokemon that rotated around his main team, and his mythical and legendarys), as well as a trio of starters he was going to let Eve/Yami choose from(the Hisuian Starters).

When he gets to earth and learns more about the situation, such as apparently some princess was planning a harem for her brother-in-law, that included HIS WIFE, AND STEPDAUGHTER, and the fact another girl, Eve's apparent sister is trying to make her revert to her weapon programming to make her a living weapon, AND HE GOES FUCKING BALLISTIC. He out right humiliates Momo about how her plans are asinine and immoral, especially when she knows that Tearju is already married to him, infront of the whole school, and faces off against Mea, dominating her with Sylveon alone.

When they first get to the school, Rei and Arcus get split up, and Arcus runs into Yami, and when Arcus asks Yami if she's Eve, she immediately goes on the offensive and attacks, due to that fact he looks like a younger boy version of her. So yeah, Yami traumatized her younger brother, and both mother and father make it clear how furious they are.

When faced with Nemesis, Rei out right fight her himself, and WINS, having developed aura and a rough fighting style that takes advantage of his immortality. He contains her for the main purpose of breaking her down and making her into proper matter, and if he can't do that, he'll just destroy her, not the first time he's killed a psycho, won't be the last.

Also, turns out Volo is cursed with immortality of his or, actually her own, because she was actually a gender confused chick who thought she had a crush on Lady Cogita, when actually she wanted to be her, she now goes by Cynthia, the SINNOH CHAMPION, and her team are actually descendants of her original team, meaning they are literally breed to perfection, no wonder she's so strong.