Ikki x Stella is not a good ship
The Ikki x Stella romance in Rakudai Kishi is the epitome of “well, that escalated quickly”. Stella agrees to become Ikki’s “slave” in the first chapter of volume 1, she services him in the bath in chapter 2, and they become boyfriend and girlfriend by the end of the first book. People like this. They call it “refreshing”.
I call it bullshit.
I can see how you might call Rakudai’s romance “refreshing” if your only exposure to romance is via harems where nobody gets together. Going by those same standards, 50 Shades of Gray is the greatest love story since Twilight. Even a cursory examination of Rakudai Kishi’s plot should reveal to you that it’s self-indulgent, masturbatory horse excrement, and that Stella is a trophy girlfriend rather than an actual character.
Consider the role that Stella plays in the narrative. She’s introduced as a super powerful A-rank knight and then promptly loses to Ikki. Other than that, she never has any major battles in the first three volumes. She constantly stands aside to let Ikki do the fighting. Some of the situations she gets into are downright exploitative too. In the first volume, she obeys a terrorist’s command to strip, and later on in the same volume she agrees to become a generic villain’s girlfriend if he beats Ikki. In terms of the actual function she plays in the narrative, she’s a damsel in distress more often than not. Her strength exists only to make Ikki look strong in comparison.
The interactions between Ikki and Stella are painfully cheesy as well. They don’t actually have conversations, they just exchange meaningless romantic platitudes. You might say that this is an accurate portrayal of a young couple, but the story clearly frames their relationship as “THE GREATEST LOVE STORY OF ALL TIME”. (Spoilers: they agree to get married at the end of volume 3 lol.)
I will give Ikki x Stella points for one thing. The story doesn’t shy away from sexuality. I quite like how Stella in particular becomes more open about expressing her sexual desires. It doesn’t make me ship the couple, but it does make me want to read the doujinshis. Comiket can’t come soon enough.
Ikki x Stella is a crapshoot, but you know what is a surprisingly good ship? Alice x Shizuku. Their relationship is understated and touching in its own way. Although Alice self-identifies as female, I think Shizuku is the only person who refers to Alice as female (iirc even the narration uses the masculine pronoun 彼). Shizuku’s comfortable relationship with her “big sister” Alice exists in clear contrast to her obsessive love for her older brother. It’s quite ironic that Shizuku experiences a more genuine kinship with someone unrelated to her through blood, but it just goes to show that relationships are what you make of them.