What does こつぐってなる mean?


What is [written here](http://viewer.comic-
earthstar.jp/viewer.html?cid=19b650660b253761af189682e03501dd&cty=1&lin=0) on
page 4, after 「それと一緒に」? I searched in WWWJDIC and Google, but I can't
understand the meaning of 「こつぐってなる」. For the 「語彙が…」 comment, I understand that
this word sounds strange for the characters too. But strange is different from
nonsense.

[![enter image description
here](https://i.stack.imgur.com/pL9F9.png)](https://i.stack.imgur.com/pL9F9.png)




You misread one _hiragana_. It says

> こ **う** ぐってなる

(So, not つ but う.)

The comment 「語彙が…」 refers to the fact that the girl is using a lot of
onomatopoeic expressions (instead of proper vocabulary) to describe the first
bite of the cake.

Here こう (sibling of そう、ああ、どう) means "like this". ぐっ **て** なる can also be
written ぐっ **と** なる and refers to some tight/cuddly/... feeling.

> この白い  
>  ふわっとしたやつが  
>  口の中でふぁーって
>
> それと一緒にこう  
>  ぐってなるやつが  
>  なんか混ざり合って  
>  ぎゅーんって
>
> This fluffy white thing is in the mouth like _*phwaaah*_  
>  Blending together with this _*uhnnn*_ and going _*mmm*_

Not an award winning translation, but I trust you get the point =)

