I have been seeing some vtuber fans that probably are still new, so just a reminder about some rules:
1. Your oshi isn't your friend, no matter how you see them. Don't @ them either on social media or their livestream chat. Unless they're okay with it, but in general please don't.
2. When you watch them, you're there in their "world". You're there to watch and supporting them. If you watch something that isn't to your liking, you can simply close the stream.
3. Every vtubers have their own rules in the description box. Please make sure to see and follow them.
4. Their livestream chat isn't your chatting box. The topic should be about the stream and your oshi, iirc some streamers have strict rules of to not @ others in chat, and to please keep personal conversations to either DM, Twitter, or Discord.
5. The hashtag is there for a reason. You can use the hashtag for putting art, asset, merchs, etc.
6. Be kind. Be respectful. Not only to your oshi but to people in the fandom.