BUR #19526 has been approved by @nonamethanks.
create alias kuroneko_(oreimo) -> gokou_ruri
Ruri's name isn't actually revealed in the series until much later after she's introduced, for a long time she's only ever referenced as Kuroneko. An alias feels useful/appropriate enough, especially for anybody newer to the series. I know it's not exactly a new one, bust still.
As an interesting addendum to this, Damian even did some helpful dives into the history of the tag on the Discord server... The light novel came out in like 2008 and her earliest posts are from around mid-2009, but she didn't even get tagged until 2011, which is about a year after the anime came out and massively increased the popularity/awareness of the series (pre-anime premiere in Oct 3, 2010, there were only 35 posts of her). By then her real name would've been known, but it's very likely that kuroneko_(oreimo) would've been created and used first as a tag if people had actually bothered from the start.
Updated