It's a webcomic that had a very, uh, devoted following among a niche crowd of mostly 14-21 year olds. It's got a lot of videogame influences, namely EarthBound and point-and-click adventure games. Toby Fox of Undertale fame did a lot of music for it,
which was pretty dope. It also means that there's a lot of overlap between the Homestuck fandom and the Undertale fandom, so... that should tell you something about what it's like.
Anyway an adventure game based on the comic was Kickstarted for $2.5 million in 2012 and has been in development hell ever since. It was originally going to be developed by The Odd Gentlemen but they dumped it to work on King's Quest instead. So creator Andrew Hussie had to start his own studio to get the thing made which meant the comic, nearing its climax, was often going on hiatus for months and months at a time while he tried to get the game under control. Undertale happened to come out during one of those hiatuses and a lot of the fanbase, frustrated with the lack of motion on the story, decided that those skeletons looked exceptionally fuckable and moved on to flipping their shit about that instead.
