This is a 90s/00s style cyberpet agency. "Cyberpet" is a word that probably brings up images of Tamagotchis or Neopets, but there was also a strong community at the time of "adoption agencies" that offered webpage pets. These were small graphics, often hand drawn or pixel art, of creatures you could adopt by displaying them on your own webpage. Cyberpets could be anything from fantasy creatures to everyday pets. Some had to be applied for and given out by the artist, but others, like this, were "click and take" meaning that anyone could adopt a pet and add it to their page. Many agencies were written in a second person style, such as: "you enter a forest, and a dragon turns to face you", giving the impression you were exploring another world to find the pet.
These are not adoptables in the modern sense. They are not "closed species", they are not exclusive, and they are definitely not for sale. They're just fun little pictures for you to collect and display.
This particular agency is mainly inspired by the The Nameless Forest, a massive text adventure in which you could explore a whole world and discover creatures as you go. Most of it is still archived at the Wayback Machine, and there's hours worth to explore.
Well, put them on your website, if you like them. (You do have a website, right?) Make up names and personalities for them. Make up a little story about how you came to another world and took them home. Or a big story. Whatever you like. Get creative, read up on the history of website cyberpets, and take inspiration. Maybe even make your own agency or webmaze.
If you want to add them to your site, make sure to save them to your own hard drive and upload them to your own web hosting, and link back to https://lilaclynx.net/hiddenworld so other people can explore too.