Hearing Navi calling for him, Link turned to her, and nodded to confirm the assertion she had made, not that it was necessary. Behind the burning cobweb was revealed to be a door that would lead them even deeper into the Great Deku Tree. They passed through and continued to search for the source of the curse that was placed on the Great Deku Tree. Eventually, Link opened another door, only to be met with the room where they started. Unfortunately, it turned out that the path they were following was actually just leading them in one big circle.
Navi let out a massive sigh, "Oh come on... Now what?" She halted her wings and dropped down onto a thick vine, causing it to droop from her weight, "Flying is way too tiring to keep going like this any longer... I'm going to rest over here for now, if that's alright with you." There were no objections from Link, not that she was expecting any at this point, so Navi laid back and began to rub her large belly. It had ballooned an incredible amount in such a short time frame, and it would certainly grow even more if she kept eating at the same rate as earlier.
While she was relaxing, Navi was starting to feel tired from all the moving around she had done. She stretched out her arms and yawned, her mouth wide open, allowing for a repeat of last time. Suddenly, another berry like the ones from earlier dropped down into her mouth from seemingly out of nowhere. Navi's eyes shot open, after swallowing the tasty fruit of course, and looked up to find the cause, that being a smaller vine she somehow hadn't noticed. It was growing even more of the small juicy berries than the last one, and the sight of so many was causing Navi's mouth to water.
Berries continuously dropped down from the vine above into Navi's mouth at a consistent rate, giving her plenty of time to chew and swallow each one. While she had learned that they were incredibly fattening, they were too delicious to pass up. Besides, they probably wouldn't be coming back to Kokiri Forest anytime soon, so she might as well enjoy them while she has the opportunity, right? As to be expected, Navi's body grew slightly with each berry she consumed, with her belly as the most prominent example, slowly beginning to spread over her thighs.
Events seemed to keep recurring, as Navi once again heard a snapping sound just like that of when Link broke through the giant cobweb before. Upon looking up again, she noticed that he indeed found another cobweb to break through, and did just that, falling down even further into the depths of the Great Deku Tree. Navi followed him down the hole once more, this time ending up in a much more straightforward room; all that was there was a single door. Navi gulped, having a bad feeling about what would be on the other side. Link didn't concern himself with that though, and entered regardless, giving Navi no choice but to follow him in.