Truth be told, I can't say I fault him much. She just held out her hands and said "here". It'd been another story if she had also said something like "Here Look! See how clear it is!". Instead her just holding out the water and saying "here", makes it seem like she was offering it to him to drink. Of course, one could say that he didn't need to drink it directly from her hands and instead could've scooped some of the water out to drink (or he could've just asked I suppose), however considering how close she gets to him, as well as how much she clings to him and gets into his personal space, it probably seemed pointless.
So honestly I say this is less of him being weird and more of him trying to respond in kind to her usual antics. Unfortunately for him, it backfired.