I don't know how I should feel about a Suzuya who's hoping to Admiral cheats on her sister. With herself, no less.
I think you might be misreading that.
She's holding a charm that implies she's romantically content, but when it's noticed, she's so embarrassed, she says she's holding it for Kumano. Kumano isn't dating the PoV character/Admiral, and Suzuya's just claiming Kumano is dating someone else (which may or may not be true).
Wassup! HNY!Let's get moving♥Hey, Admiral...T-This is Kumano's!!
Not Suzuya's, see!
You're mistaken, yeah!?May I get praised even more!
May I get even cuter!
May I get more honest!And may he fall even more and more and more in love with Suzuya than he is now!!Have you been planning on breaking it off with Suzuya soon?
That's not on the cards, right??HAH!?You're mistaken!!* Love: Signs point to interlopers, be careful.Romantically content