Ibuki appears to be attracted to Peko. In Chapter 1, when Peko offers to be on guard duty and leaves the room, Ibuki grins and mutters to herself that she feels Peko has "this super cool, melancholy vibe".
In a Special Event during the first chapter, the two are walking together on the beach when they meet Hajime, Kazuichi and Teruteru. Ibuki winks and claims she was holding hands with Peko, though Peko stoically denies this and tells Teruteru not to fantasize about weird things when he imagines the two girls having sex. When Peko talks about splitting open a coconut and describes how she wouldn't make a mistake with a sword, Ibuki gets really excited, screaming that she's so cool and that she might fall in love with her quiet words. She then begins to call her "Peko-Peko", but Peko seems to mostly ignore her behavior.
In Chapter 2, Peko arrives in a swimsuit at the diner to meet up with the other girls to go swimming. Kazuichi is there and says to Hajime that a woman with wet, slicked back hair is pretty nice. Ibuki adds on by saying her body is pretty fine too.
In Ultimate Talent Development Plan, after the Winter closing ceremony, Ibuki asks Peko to walk home together. Ibuki tells Peko that even though Christmas was just yesterday, she's all ready for next year's. Peko says that the party they had was fun, but thinks that Ibuki is getting ahead of herself. However she agrees that it was enjoyable, which makes Ibuki happy. The two promise that they'll both come to next year's gathering.
Ibuki is loud, cheerful and goofy, while Peko is calm, quiet and serious. Some fans consider this a perfect example of the Opposites Attract trope. The ship mainly caught attention with the special event in chapter one, mainly because of Ibuki claiming she held hands with Peko, and the latter telling Teruteru not to get perverted thoughts about the two.
Aesthetically, the similarities of their character designs are able to contrast and match to make edits and clothing swaps. Both have white/gray in their hair, a navy pleated skirt, white shoes, and wear a sailor-style uniform. Ibuki's outfit has pinks and blues while Peko only has red. These similarities in differences even only in their clothing is attractive to some.
- They seemingly died back-to-back, until the reveal that Ibuki was actually the second victim of the double victim case in Chapter 3.