What exactly does "るぅ" mean?


Good afternoon all,

Sometimes I see that people like to "curl" the last mora of a verb, for
example:

> 瑞生: ああそれから、亜湖にも特別ボーナスだ。
>
> 亜湖: えっ。
>
> 瑞生: ジャーン！
>
> 亜湖: 何それ？
>
> 瑞生: かわいいだろう？
>
> 瑞生: おいおいおい、ほら、ちょっと、当ててみろよ。
>
> 亜湖: 何？
>
> 瑞生: ほらほらほら…。
>
> 瑞生: わあ、似合ってるぅ！

([Youtube
link](http://www.youtube.com/watch?feature=player_detailpage&v=B2CS7yKO8T8#t=551s))

I was wondering what exactly does it mean to curl the "る" sound of the verb,
and in what situations do we do that?




It makes it feminine and cute. It may imply that the pronunciation is done
with
[アヒル口](https://www.google.com/search?q=%E3%82%A2%E3%83%92%E3%83%AB%E5%8F%A3&hl=en&prmd=imvnsl&source=lnms&tbm=isch&ei=6piCT_-
gNuXq0gHo4oCbCA&sa=X&oi=mode_link&ct=mode&cd=2&ved=0CBcQ_AUoAQ&biw=666&bih=662)
(duck mouth).




It makes it feminine and cute. It may imply that the pronunciation is done
with
[アヒル口](https://www.google.com/search?q=%E3%82%A2%E3%83%92%E3%83%AB%E5%8F%A3&hl=en&prmd=imvnsl&source=lnms&tbm=isch&ei=6piCT_-
gNuXq0gHo4oCbCA&sa=X&oi=mode_link&ct=mode&cd=2&ved=0CBcQ_AUoAQ&biw=666&bih=662)
(duck mouth).

