One: Kaga's admiral seems like a grown-up version of the admiral from the very first page in this comic.
Two: I think it's safe to assume that Kashima quit being a shipgirl soon after her near-rape by that shitty admiral, because if merely seeing an admiral's cap immediately reminds her of said shitty admiral, then it seems she never managed to have a positive experience with a more upstanding admiral after her trauma.
Three: I predict that Kashima actually kept the near-rape a secret from everyone (including Kaga), and the next scene in this restaurant will have the shitty admiral who nearly raped her arriving because Kaga's admiral invited him to this dinner for one reason or the other, completely unaware of the bad history between the guy and Kashima.