(comment spoiler warning:)
I felt the same way. This game left no solid answers as to why everything happened which is different from how this author usually makes their games, so it caught me off guard. We could reasonably assume something like a mass hysteria caused by the drinks maybe, but somehow June was unaffected even though she drank some. There was no solid reason as to why she was the only safe one. I would have liked something a little more to help tie it all together, like how were the behavioral changes connected to the ocean? But even though it didn't answer everything, in a way not knowing also made this feel more like I was experiencing what June was experiencing, horror through not knowing, desperate to help her friends but clueless as to how.