she definitely would've had a huge following as people in fandoms just FLOCKED and IDOLIZED these canon url accounts, making them essentially Tumblr microcelebs.
I know I'm late to this a bit, but i was a 14 yo homestuck tumblr baby (very deep in the lore, and i recognize this account lol) and I can verify 100% that this was a thing. Being a child on the internet, its really easy to conflate the tumblr account with the actual character. If you had the davestrider account, you WERE THE dave strider. Even I felt jealous of and looked up to/idolized those with canon URLs. If her url were anything else, young girls wouldn't have randomly sent in cuddle applications seeking validation from an internet rando.
In addition to this, the entire homestuck fandom was completely hypersexual in some way, shape, or form. The normalization of how sexualized things were in the homestuck fandom made a safe space for predators. Especially at conventions, where it was completely normal to see teen girls sitting on older men/women's laps because they were cosplaying characters that they shipped together.
In my opinion, there is no way that Necky 's fiance didn't know the influence she had in that fandom and didn't abuse it. Who knows how many "selfie submissions" she anonymously received and kept that might have been inappropriate.
Sorry for the long post. I felt like it was important for you guys to know that she 100% knew what she was doing as an adult in that fandom