I recently discovered a manga series called Wonderland by Yugo Ishikawa.
The series is a horror story about a girl named Yukko who wakes up and discovers that she has been shrunk down to a few inches in height. At first she thinks that she is simply dreaming but soon discovers that not only is it reality but she isn't the only person to have shrunk.
Everyone in a section of the city have also shrank to the same size and are being picked off by birds and cats. Not only that but the Japanese Military is hunting down the shrunken citizens for nefarious reasons. Yukko seems completely lost in all of this until she discovers a mysterious young woman with cat eyes and fangs named Alice.
At this moment in time four out of the six volumes have been released in English. The next two chapters are being released within the space of six months and that'll be it for the series. It seems to be one of those single arc series. To read online follow the links below....
https://kissmanga.com/Manga/Wonderland (English, incomplete)
https://lhscan.net/manga-wonderland-raw.html (Japanese, complete)
For GTS fans, in volume four both Alice and Yukko do become giant size.