The anime differs from the manga, in the way certain characters are portrayed and by substituting filler arcs in place of some of the manga's key story events:
character specific changesTakeru
- Manga: Minori begins training him during the Okino Island chapters (28-30) and in chapter 53, Himegami reveals that Takeru's Blood Pointer ability is proof that he's distantly related to her father and brother, who also possessed it.
- Anime: He's only briefly seen training in episode 13 and the reveal about his connection to Himegami happens much earlier (at the end of episode 4), where she says he's her brother's reincarnation, rather than his descendant.
- Manga: While it's initially implied that she was killed at the end of her duel with Tesshin, he later explains that Atsuma was already dying at the time of their fight. It was the long-term effects of using her Blood Pointer that actually killed her.
- Anime: The man she's seen fighting during the flashback in episode 12 isn't Tesshin and it's all but stated that Atsuma was beaten to death. Whereas the manga shows she survived the match and died sometime afterward.
- Manga: She drives the plot, complete with her own character arcnote and she's Usui's love interest.
- Anime: She has no plot relevancy and her past is never revealed. Instead, she's reduced to being another member of Takeru's harem.
- Manga: She became a lesbian after suffering a traumatic event that left her androphobic.
- Anime: Her phobia is downplayed to the point of being almost nonexistent, to have her instantly become smitten with Akaya. It's only referenced indirectly during episode 9 (season 2), in which Yuuka sets her up on a date with Azukinote to try to help Takaki face her fear.
- Manga: Her heart (and her loins) are set firmly on Haruko.
- Anime: During season 2, she comes to accept that Haruko is in love with Takeru and gives up trying to pursue her.
- Manga: She's fully aware of how the male students think of her and is shown to be self-conscious because of it.
- Anime: Complete 180º, she has no idea — even when they're blatantly staring at her chest, or looking up her skirt.
- Manga: She's a high-ranking member of the Shishigami, second only to her grandfather, Ouken. She's also shown to be indifferent towards Akaya, since he and the Venus Unit serve her family.
- Anime: Otohime is a bit character and Akaya has authority to go above her head, to force her to stand down in episode 12.
plot related changesChapter 8
- Manga: Yuuka prevents Azuki and Yan-Min from fighting by proposing they settle their dispute with a contest instead. So she sets up a hockey match in the pool to manipulate both teams into cleaning it, then set the rules to ensure the match ended in a draw. The chapter also showcases the Venus Unit's level of coordination and teamwork.
- Anime: They settle it with an indoor volleyball match instead, which served no purpose other than to show off both team's level of power. It ends with Yuuka simply declaring it a draw, once the gym gets destroyed.
- Manga: Akaya has the Twins capture Himegami, then uses her as leverage to coerce Haruko, Inaho, Azuki, and Takeru, to battle the Venus Unit — so he could assess the Tenbi students' level of ability.
- Anime: The entire arc is replaced by a 2-episode finale, in which Haruko is abducted by Otohime Yamato. After being rescued by the Venus Unit, they open a portal for her so she can hurry back to the Academy in order to save it from Takeru, who'd become possessed by his Blood Pointer ability.
- The OVA loosely adapts the same story, but makes the following changes:
- Celia uses Inversion on Takeru in a fit of jealousy, after catching him on the couch with Ms. Akinote .
- When Takeru regains consciousness and realizes he's been turned into a girl, he's shockednote .
- Adds scene of Takeru trying out her new body by masturbating in the bathroomnote .
- Adds a bath scenenote .
- Scene where Haruko wakes up and finds girl-Takeru sleeping facedown between her legs, changed so Haruko shoves her away when Takeru wakes up and tries to suck her breastnote .
- Celia tells Takeru he has to kiss a girl to undo the Inversion's effectnote .
- Near the end, the girls take turns smacking Takeru around the room, causing him to repeatedly change gender each time he kisses one of themnote .
- It ends with Haruko kissing Takeru on the cheek to change him back, once the other girls are gone. Though the stinger reveals Usui had also been affected by Celia's Inversion and is still a girlnote .