提督にお願いされて想像で塩対応をする霞ちゃん

Kasumi-chan's guess at what it meant when the Admiral said he wanted a "salty interaction".
Like the "previous strip,":/posts/3573030 this is a pun on the idiom of a "salty interaction". It's a term that apparently is in popular use regarding "idols that act cold towards their fans,":https://tokyogirlsupdate.com/salty-idols-20150959681.html so presumably the Admiral likes idols who are cold towards their fans.