[Raion]

For those not familiar with this purely Japanese trend, a "VTuber" is a "virtual youtuber". Basically, the entire craze started with:

Kizuna Ai

Kizuna Ai is a self-proclaimed AI youtuber, but in this case it's actually a voice actress/performer using Unity+Motion Capture to present herself as a 3D model. She does activities, lets plays, singing, and discussions on her youtube channel, and she's kind of set the trend:



The appeal is that she's made this exaggerated portrayal of a naive, child-like AI and that sparked the VTuber movement. 

I do sometimes watch Kizuna, but she's a bit flat compared to some others. 

The one I was recommended by my friends, and now me and the SO watch together, are HimeHina:



Example above. HimeHina is a Japanese duo consisting of "Hime Tanaka" and "Hina Suzuki" (obviously not their real names) with very contrasting styles, looks and personalities. 

Hime is dressed in a very neo-Taiwanese/Chinese style is the "head" of the group and is probably the more excitable, comedic, loud and crazy of the two.

Hina is dressed in a more Japanese-style, with lots of military theming, and she's the supporting member. Far less excitable, and more "calm and cool". 

The funny thing is that both are... well not exactly well-educated. They're both airheads, and regularly get Japanese literacy marks that my friend who teaches japanese probably indicates they're high school dropouts. 

The overall trend is just female (and occasional male) youtubers who model themselves into an anime-style and perform comedic activities. This has been quickly commoditized by Japan, as there's now networks and Idol-like groups and management for these creators, encouraging things like singing and other entertainment. 

It's an interesting one, and sometimes you question your use of your time, but I don't mind that much.