Anyone else enjoy picking sun signs for their favourite characters of unknown birthdate based on the traits they show? I'm not even a believer, really, I just love picking out the patterns, and I feel that in a properly organised universe astrology would work. Which is a statement which ironically screams Virgo.
...I came in thinking this would be about the signs in things like The Elder Scrolls, Dragon Age, or the Tolkien Legendarium. Whoops. Not quite that it seems. I've never really tried picking signs for people with unknown birthdates now that I think about it. Huh. I can definitely get doing it because you like patterns though. It's why I like to assign classpects or MBTI to characters I like. Nice and neat tidy things in boxes yes.
I'm not really in the habit of doing it for other fictional characters, but I have the sun/moon/ascendent signs for all my characters determined because I love interpreting characters through different lenses like that -- like Aondeug said, nice neat and tidy things in boxes, just like classpects and Hogwarts houses and so forth. (I actually specifically picked up the habit from a friend who does it. ...I laughed when she said she couldn't tell me her characters' moon signs because they implied spoilers, and now I have the same problem.)
I do that all the time, especially with ocs. I think some even have a full BC, with aspects and everything.
I may or may not have put birthdays depending on the type of person I wanted my character to be. (*coughs*Tyven*coughs*)
Key and I did that with a bunch of characters in Maria. I think we started with the Chinese Zodiac and wound up doing a bunch of research into cut-off dates because our two main characters are in the same school year but we decided their personalities are way too different for them to have the same sign. We decided month/day using the tropical zodiac, though. @Aondeug MBTI for characters is so fun! When I use it I usually write the character however I want for a while, then take the test for them, then flesh them out more with the test results in mind.
Yeah, I usually determine my character's birthdates based on the sun signs and moon signs I want them to have. I also love taking the MBTI and enneagram tests in character (and sometimes taking one that is 'character answering as they would self-report, not as they actually are') and keeping that information in a little bag of quirky information to have.