Shunsuke’s and Hinaki’s relationship are more sibling-like than friends. Hinaki shares an umbrella with him, takes a bath at his place, and lays around his room in loungewear… and the man is completely unfazed. Even in a previous chapter he sees her panties and doesn’t care. He’s pretty much immune to all the rom-com tropes.
However, the moment he mistakes her for Kiyoka he gets hot and bothered.
I’m hoping there will be more tension between the trio because Shunsuke loves Kiyoka, Kiyoka is becoming more aware of loving Shunsuke, and Hinaki displays every quality of loving Shunsuke without saying it’s love. Each of them have their own unique problems but Kiyoka and Hinaki have more interesting plot to uncover.