EN Vtubing for people that don't watch Vtubers.
So, someone you know sent you Ironmouse's video about quitting Vshojo, but when you ask for context you just end up more confused. Here's a little glossary to explain the context of some of the names and words you'll hear. This is not an exhaustive list but it is accurate to the best of my ability and should provide most of the necessary context to what's going on.
Vtuber: short for Virtual YouTuber, a Vtuber is an individual who streams/creates content but rather than showing their face they use an Anime style avatar and mapping software that allows the avatar to move along with their body to mimic their real movements. Often a Vtuber does so as a character with a specific backstory rather than just as themselves.
Liver/talent: the individual who provides voice and motion capture for a Vtuber character. While references to a Vtuber is often used synonymously with that Vtuber's liver this is not always the case.
Past-life: the character that a specific liver used to perform as, but does not do so anymore. This is usually in the context of an indie Vtuber joining an agency, but is less often used to mean an agency Vtuber going indie.
Agency: a company who manages multiple Vtubers, owns or manages the relevant IPs for those characters and employs livers to stream as said Vtubers.
Indie: a Vtuber which is directly owned by its liver and is not affiliated with any agency.
Graduate/Graduation: the retiring of an agency Vtuber. Said Vtuber's liver may be leaving the scene and retiring altogether or may be going indie or to another agency. A graduation stream is the last stream a liver performs as said Vtuber. If a liver is fired or leaves without graduating it's considered an act of disrespect on one or both sides.
Hololive: a Vtuber agency, one of the first pioneers into EN (English) Vtubing. They are currently one of the largest agencies worldwide and in the EN space specifically.
Nijisanji: often abbreviated as just Niji, Nijisanji is one of the other largest vtubing agencies in the world and until very recently was also one of the biggest VTuber agencies in the EN space. Niji's relevance and popularity has dwindled in recent years after the mass graduation of their top talents and a major scandal involving EN vtuber Selen Tatsuki being pushed out of the company without graduation. Selen's pastlife Dokibird would allude to extreme bullying and direct managerial sabotage as being part of the buildup and would later re-debut as an indie with massive community support. Nijisanji as a result has a reputation as a 'black company' a Japanese term for an exploitative workplace.
Vshojo: a Vtuber agency founded on creative freedom for talents, including contracts which grant talents ownership of their Vtuber in the event that they leave the company. They are currently in hot water for not paying their talents and refusing to pay out money that was raised by Ironmouse, their biggest vtuber, for the Immune Deficiency Foundation.
Phase Connect: a Vtuber agency largely considered to be the first EN Native Vtuber agency. They are also frequently called the sadgirl company or menhera company because their Vtubers have a tendency to act particularly unhinged in comparison to other agency Vtubers. They're also sometimes called a coffee company because one of their primary merch lines is a line of coffee, and they once made an April Fools announcement that they were quitting Vtubing to become a full time coffee company.