In simple English, the context of the image seems to be something like this: Warspite brings Pola her wine saying, "Here's you're wine, take it." Pola interprets this as, "Take it in the ass," considering her history with British ships.
You want to insert that wheeeeeere!?
According to the image, Warspite seems to be bringing Pola her provisional wine (差し入れ - sashiire). However, this sounds the same as "inserting something into something" (挿し入れ - sashiire). Pola interprets it as the latter.
