Yeah, this happened with me too.
I developed an obsession with the character Bridget from a game called Guilty Gear, a good number of years ago. It led to some of the usual sorts of things... I have pictures and multiple figures of the character, for instance... but it also led me to places I never could have expected. I started to do a cosplay of the character (if you dont know what that is, it's the act of dressing up as any specific character, typically while at an anime convention or something like that) which furthered that connection. But as this required going to anime conventions to do, I started doing that... and that changed so very much. Up until that point, I'd never traveled on my own, really. That first convention was my first time heading off to a hotel on my own without my family, and it was a very new experience. Later that year I went out of state (to Iowa, coming from Illinois) on my own for the first time; that first time was a trip by bus, but that specific convention has become a yearly thing, and I now drive out to Coralville, Iowa, each time for that particular event. Various other conventions take place in assorted places in Illinois or Wisconsin. I started to gain a real appreciation for travelling because of this, and became a heck of alot more comfortable going places on my own. These days, if I get bored enough, I'll even do things like go find random country roads I've never seen before, and drive down them just to see where they go, and then maybe find more roads and go down THOSE to see where they might lead. I never would have been bold enough to do that before all this started, but all of that travelling showed me that new places could be really interesting.
This also led to me gaining the confidence to really be myself instead of always trying to fit in, in ways that I never actually wanted to (yet would of course do anyway, because society said so). This came as a result of doing the cosplay bit... the outfit is a strange one, and not exactly something a male would normally wear, but I didnt give a crap and wanted to do it anyway. Much to my surprise, people liked it instead of laughing at me. Turns out that sort of thing suits me. With that, I started to get more and more confident to just be myself instead of trying to be something that I just am not. Even my day-to-day appearance has changed as a result of this, and I no longer loathe the way I look. Usually.
And lastly, various events that occurred as a result of all of this led to me meeting new people... and more importantly, making LASTING friends that I've now known for years. And I mean REAL friends, the sort that completely accept me for who I am, and who also can deal with my autistic tendencies (for example, they *never* push me to be social when I dont want to, because they know I dont like that... but if I want to join in an event, they never exclude me, either).
It all really led me to places I never could have expected. And that's just that obsession. Or "special interest" as we often call these. I have others... video games in general, and game design, THAT recently took me through some very interesting experiences, where I learned quite alot and finally got to ACCOMPLISH something. Or my interest in "twisty puzzles"... think something like a Rubik's Cube, except much, much crazier (a normal Rubik's Cube is very easy to me, now). I have like 120+ different puzzles now, and they give me something to do that engages my mind while NOT being related to this blasted computer. So that special interest also has a use (and my family finds that one particularly interesting, they like that it gets me away from the PC, and they also just find it neat that I can solve such things and think that the puzzles are interesting to see).
All in all, it really just shows that you never know where something like this can take you. We can latch onto basically anything as an obsession (it's not always something like characters from TV or games, it could be something like, say, vacuum cleaners for instance, and that's not one I'm making up, I recall reading a story about someone with Asperger's that had that particular obsession). There's all sorts of interests.
And as long as it's not causing bad things in the person's life, I've always thought there's no harm in it. Particularly if it ends up causing unexpected good things, as mine did.
Plenty of people might think stuff like this is weird, sure. But the way I see it, the usual definition of "normal" is boring. I'm not interested in being "normal". I, personally, will stick with "weird", thanks. It's so much more interesting...