https://marshmallow-qa.com/irinakumai call her out on marshmallows, its free use and anonymous, she can block your IP and AI moderation might catch your message, don't send links she won't open them.
enough hate marshmallows and she'll close them down, making even her fans angry at her
best ways to get under a vtuber's skin is telling them they can't sing, that their voice sucks and that they are boring and should give up.
if you want to just spam, spam the emails.