Archive of Our Own

Premise:

When Subaru was sent to the Re:Zero world, he was given everything he had from his Infinite Dendrogram account as Natsumi Schwartz. And yes, he is still in his normal self and not in his avatar's body. This includes his items, his gear, his MVP reward items, his tamed spirits and lastly his Superior Embryo. He still has Return by Death, but he doesn’t need it. He does find out about it and uses it in Arc 3 but only once.

Subaru’s Embryo:

Type Maiden with Guardian/Arms: Maiden of the Depths: Jörmungandr

Weapon form: 1st through 3rd; a snake skin whip, 4th through 6th; a snake that tail ends in a whip handle that can move on its own but still needs Subaru’s input on where to attack, 7th form; a massive serpent that’s body is the width of a carriage and a head big enough to swallow one whole.

Ultimate skill: Serpent that Envelops the Globe: Jörmungandr. Lengths the snake's body to allow it to destroy anything weaker than it in one go. In Arc 3, Subaru first uses it to latch on to the white whale and pull it down and hold it there so the rest of the army can wail on it.

Human form: A young girl who looks to be younger than 10. She has green silver hair and an angular face like a snake with again snake-like yellow green eyes. She wears a white poncho with black snake patterns on it, that cover most if not all of her skin. Under her clothes, she has patches of snake scales on her skin. Her Maidenly eating habit is that she can only eat with her hands, so she is kind of a clean freak when it comes to washing hands. Her nickname is Jörm.

Subaru’s Jobs:

1. Low rank job: Whipmaster: Waited for his Embryo to hatch before he got his job so he would have to get a different one if his Embryo was the opposite of what build he wanted. And since his Embryo was a whip, Whipmaster made the most sense.
2. Low rank job: Spirit Tamer: After maxing out Whipmaster and finding out that he was naturally gifted with Spirits, Subaru got the Spirit Tamer job along with his first two spirits.
3. Low rank job: Knight: Subaru wanted the knight job for three reasons. First, the job had a lot of good skills and abilities along with making his build more durable. Second, he wanted to try and see if it would unlock any mixed high rank jobs. And thirdly, he just thought being a knight would be cool.
4. Low rank job: Scout: Got it to give him appraisal and its other survival skills.
5. Low rank job: Mage: Like with Knight, got it to get another high rank job and to give him some more firepower.
6. Low rank job: Tailor: Got it after his Superior Job as both a hobby, a way to make outfits for his spirits and as another way to make money.
7. High rank job: Spirit Knight: After maxing out Knight, Subaru discovered what he had been hoping for, a lost mixed high rank job and got it immediately.
8. High rank job: Spirit Mage: Got it after maxing out his Mage job and contracting his third Spirit, Nova
9. Superior rank job: Spirit Sage: Can only be acquired by having both Spirit Knight and Spirit Mage. It is a mainly support job for his spirits and Subaru mostly lets his girls do half of the fighting, so he found that it was a good fit for him.

Subaru’s Spirits and Tames:

1. Water Spirit, Aquarius: The first Spirit he contracted and in the time since their contract she and his second Spirit have both become high ranking spirits. She looks like your stereotypical shy little girl with long blue hair tied into pig tails with blue eyes hidden by glasses. She is the most level-headed of his spirits.
2. Earth Spirit, Terra: Like mentioned before, she was contracted alongside Aquarius and became a high-ranking spirit at the same time as her. Her human form looks like a young tomboy with tan skin, short blond hair and brown eyes, and a toothy grin. She is the one who doesn't know how to keep still and is basically a little girl version of Garfield. Also, she is the one who came up with the idea for Subaru’s spirits and Jorm to call themselves the Pleiades 7 and act like a super Santai group (or in the America’s power rangers).
3. Fire Spirit, Nova: Subaru’s third Spirit and the only one that was already a high rank Spirit when he got her. She acts like your standard stubborn, hotheaded, princess little girl that needs someone to help rein her in when she gets into it. She looks like and dresses like a young noble woman who thinks she is above everyone around her except for her parents, or in this case Subaru.
4. Beatrice: Subaru contracted with her like in the main story but this time it was because Nova managed to get her to realize what Echidna meant in her contract with Beatrice about who that person was. And because Nova and Terra had been pressuring Beatrice to join as the Pleiades 7.
5. Zarestia: At some point, Subaru goes to Banan and meets Zarestia and gets her to become one of his spirits. She also ends up joining his harem.
6. Shaula: At some point like with Zarestia, Subaru ends up at the Pleiades Watchtower and Shaula joins both the Pleiades 7 and Subaru’s harem without complaint.

Relationships:

Most of the relationships are the same as in canon with the only difference being that Subaru gets a harem. The girls in said harem who are in the Royal Selection make a bet that whoever wins the selection gets to be his head wife. Here is the list of who falls in love with Subaru and joins his harem and the reasons for the one I figured out:

1. Emilia: Fell in love during their date in between Arcs 2 and 3 but didn’t realize her feelings for Subaru during Arc 4
2. Rem & Ram: Fall for him during Arc 2
3. Crusch: Falls for his during the battle with the white whale and when she first meets him again after losing her memories from Lye
4. Priscilla: Fell in love with him because she found him amusing and it evolved from there
5. Zarestia
6. Shaula
7. Frederica

Trivia:

1. Subaru’s home country was Legendaria, the land of fairies and perverts. Subaru didn't tell anyone about this when he arrived in the Re:Zero world, mostly out of shame.
2. Subaru’s avatar was, you might have guessed it, a girl. Mainly because he didn’t want to be associated with his father when he first started to play but at the current point in the story, he regrets not making his avatar the same as how he is in real life as he has made up with his parents. And again he is in his normal real live self when he gets sent to the Re:Zero world not his dendro avatar.
3. Like in canon, Subaru in Dendrogram was called the Lolimancer because all of his Spirits and his Embryo are little girls and it just kind of stuck. And while most people outside of Legendaria think he got his name because he is a freak that likes little girls, the people in Legendaria and some of his friends in other countries know that he likes girls in his own age range.
4. A running gag for this Idea is that whenever the Pleiades 7 come out of their jewel, they do a Super Santai introduction and before anyone can call them out about there not being 7 of them the all in unison yell out: "Actively Recruiting!"
5. With the exception of Subaru’s outfit (A black cloak), all of Subaru’s UBM reward items are stuff for his Spirits and Jorm and they are mostly magical girl and Super Sentai stuff from magic staffs to power ranger weapons.
6. Also, during the story any of the three great Witch Beasts get killed they turn into a MVP reward item. While Subaru is given no explanation, in the background the control AIs are in a tizzy as the Re:Zero world is slowly merging with their game world and that is making somethings cross over, like the three great witch beasts becoming UBMs. Anyway, Wilhelm gets the White Whales MVP reward, since the Great Rabbit was sent to the shadow realm nobody got anything for it, and in between Arcs 4 and 5 Subaru killed the Black Serpent and it’s MVP reward item became a set of fangs for Jorm and gave her a skill like Shu’s Ragnarok skill in Dendro. The skill is inspired by how Jorm and Thor kill each other during Ragnarok