I see what you’re getting at but to be honest, most people not listed (besides Kanade, who holds a special place in Ena’s heart) just don’t know her that well. So I feel like she’s just being polite. Ena banters with everyone she is close to, including Airi. So I do think she is just Like That
That being said,,, I do agree that her reputation is thrown off by those three because they mess with her on purpose unlike the rest of her friends. So she isn’t a tsundere, but I wouldn’t say she’s a total sweetheart
so funny how ena comes across as this angry tsundere but she's actually a total sweetheart to everyone who isn't mafuyu, mizuki, or akito. it just so happens that those are 3/4 of the people she interacts with the most.