This character represents the site/app itself, and is used for both the tutorial and in ads. In the tutorial, she's bubbly, friendly, and a little bit excitable. In the ads, she's confident to the point of being kind of obnoxious, because I've got thirty seconds to explain a cool feature of the app while also landing at least one joke, and those writing constraints lead to a very specific kind of dialogue.

I'm also realizing a day after publishing that "-tan/-chan" may not be the right Japanese suffix and I really should've double-checked this. I'd always seen that suffix used to indicate an athropomorphization of something, like a website or a planet or something. Further research indicates it may be meant to indicate childishness in particular. The mascot character is energetic and excited, but she's also supposed to come across like she's in her early to mid twenties.