You decide to proceed cautiously. You don't want to alarm the other being by contacting it prematurely, as you really don't know what the rules of engagement are on this new plane of existence. On the other hand, you can't just ignore the first being you noticed besides yourself in this realm.
You try and use your senses to tell how big this being is, but you don't have any senses that you are accustomed to using. You could, but that would require launching yourself out of the void and into something far more substantial. But wait, if you are sensing another being in the void, then wouldn't that nullify the void? Rather, wouldn't the mere presence of you and another being imbue this void with un-voidlike properties?
You are in a quandary. How can you "be" in a void?