This character is a Other Symbol and is commonly used, that is, in no specific script.
The glyph is not a composition. Its East Asian Width is wide. In bidirectional text it acts as Other Neutral. When changing direction it is not mirrored. U+1F9AE offers a line break opportunity at its position, except in some numeric contexts.
The CLDR project calls this character “guide dog” for use in screen reading software. It assigns these additional labels, e.g. for search in emoji pickers: accessibility, animal, blind, dog, guide.
This character is designated as an emoji. It will be rendered as colorful emoji on conforming platforms. To reduce it to a monochrome character, you can combine it with Variation Selector-15: 🦮︎ See the Emojipedia for more details on this character’s emoji properties.
The Wikipedia has the following information about this codepoint:
Guide dogs (colloquially known in the US as seeing-eye dogs) are assistance dogs trained to lead blind or visually impaired people around obstacles. Although dogs can be trained to navigate various obstacles, they are red–green colour blind and incapable of interpreting street signs. The human does the directing, based on skills acquired through previous mobility training. The handler might be likened to an aircraft's navigator, who must know how to get from one place to another, and the dog is the pilot, who gets them there safely. In several countries guide dogs, along with most other service and hearing dogs, are exempt from regulations against the presence of animals in places such as restaurants and public transportation.